Difference between revisions of "World Wide Web" - New World Encyclopedia

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{{Portal|Internet|Crystal_Clear_app_browser.png}}
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{{dablink|"The World Wide Web" and "WWW" redirect here. For other uses, see [[Web]] and [[WWW (disambiguation)]]. "Web surfing" redirects here. For the Web browser, see [[WorldWideWeb]].}}
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[[Image:WWWlogo.png|thumb|120px|WWW's historic logo designed by [[Robert Cailliau]]]]
  
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:''"The Web" and "WWW" redirect here. For other uses, see [[Web]] and [[WWW (disambiguation)]]. For the world's first browser, see [[WorldWideWeb]].''
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The '''World Wide Web ''' (commonly shortened to '''the Web''') is a system of interlinked [[hypertext]] documents accessed via the [[Internet]]. With a [[Web browser]], one can view [[Web page]]s that may contain [[writing|text]], [[image]]s, [[video]]s, and other [[multimedia]] and navigate between them using [[hyperlink]]s. The World Wide Web was created in 1989 by [[England|English]] scientist [[Tim Berners-Lee]], working at the [[CERN|European Organization for Nuclear Research]] (CERN) in [[Geneva]], [[Switzerland]], and released in 1992. Since then, Berners-Lee has played an active role in guiding the development of Web standards (such as the [[markup language]]s in which Web pages are composed), and in recent years has advocated his vision of a [[Semantic Web]].
  
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[[Image:NOAA Internet example.gif|thumb|350px|Today, the Web and the [[Internet]] allow connectivity from literally everywhere on earth—even ships at sea and in [[outer space]].]]
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==How it works==
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[[Image:WWWlogo.png|thumb|120px|right|WWW's historical logo designed by [[Robert Cailliau]]]]  
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Viewing a [[Web page]] on the World Wide Web normally begins either by typing the [[Uniform Resource Locator|URL]] of the page into a [[Web browser]], or by following a [[hyperlink]] to that page or resource. The Web browser then initiates a series of communication messages, behind the scenes, in order to fetch and display it.
  
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The '''World Wide Web''' (or the "'''Web'''") is a system of interlinked, [[hypertext]] documents accessed via the [[Internet]]. With a [[Web browser]], a user views [[Web page]]s that may contain [[writing|text]], [[image]]s, and other [[multimedia]] and navigates between them using [[hyperlink]]s. The Web was created around 1990 by the [[England|Englishman]] [[Tim Berners-Lee]] and the [[Belgium|Belgian]] [[Robert Cailliau]] working at [[CERN]] in [[Geneva]], [[Switzerland]].  Since then, Berners-Lee has played an active role in guiding the development of Web standards (such as the [[markup language]]s in which Web pages are composed), and in recent years has advocated his vision of a [[Semantic Web]].
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First, the server-name portion of the URL is resolved into an [[IP address]] using the global, distributed [[Internet]] database known as the [[domain name system]], or DNS. This IP address is necessary to contact and send data [[Packet (information technology)|packets]] to the [[Web server]].
  
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==How the Web works ==
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The browser then requests the resource by sending an [[Hypertext Transfer Protocol|HTTP]] request to the Web server at that particular address. In the case of a typical Web page, the [[HTML]] text of the page is requested first and [[Parsing|parsed]] immediately by the Web browser, which will then make additional requests for images and any other files that form a part of the page. Statistics measuring a website's popularity are usually based on the number of '[[page view]]s' or associated server '[[Hit (internet)|hits]]', or file requests, which take place.
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Viewing a [[Web page]] or other resource on the World Wide Web normally begins either by typing the [[URL]] of the page into a [[Web browser]], or by following a [[hypertext]] link to that page or resource. The first step, behind the scenes, is for the server-name part of the URL to be resolved into an [[IP address]] by the global, distributed [[Internet]] database known as the [[Domain name system]] or DNS. The browser then establishes a [[Transmission Control Protocol|TCP]] connection with the server at that IP address.
 
  
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The next step is for an [[HTTP]] request to be sent to the Web server, requesting the resource. In the case of a typical Web page, the [[HTML]] text is first requested and [[Parsing|parsed]] by the browser, which then makes additional requests for graphics and any other files that form a part of the page in quick succession. When considering web site popularity statistics, these additional file requests give rise to the difference between one single '[[page view]]' and an associated number of server '[[hits]]'.
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Having received the required files from the Web server, the browser then [[Layout engine|renders]] the page onto the screen as specified by its HTML, [[Cascading Style Sheets|CSS]], and other Web languages. Any images and other resources are incorporated to produce the on-screen Web page that the user sees.
  
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The Web browser then [[rendering (computer graphics)|renders]] the page as described by the [[HTML]], [[Cascading Style Sheets|CSS]] and other files received, incorporating the images and other resources as necessary.  This produces the on-screen page that the viewer sees.
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Most Web pages will themselves contain [[hyperlink]]s to other related pages and perhaps to downloads, source documents, definitions and other Web resources. Such a collection of useful, related resources, interconnected via hypertext links, is what was dubbed a "web" of information. Making it available on the Internet created what [[Tim Berners-Lee]] first called the '''WorldWideWeb''' (a term written in [[CamelCase]], subsequently discarded) in [[1990]].<ref>"[http://www.w3.org/Proposal.html WorldWideWeb: Proposal for a HyperText Project]", Tim Berners-Lee & Robert Cailliau, 1990</ref>
  
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Most Web pages will themselves contain [[hyperlink]]s to other related pages and perhaps to downloads, source documents, definitions and other Web resources.
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==History==
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{{main|History of the World Wide Web}}
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[[Image:First Web Server.jpg|thumb|This [[NeXTcube]] used by [[Sir Tim Berners-Lee]] at CERN became the first Web server.]]
  
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Such a collection of useful, related resources, interconnected via hypertext links, is what has been dubbed a 'web' of information. Making it available on the Internet created what [[Tim Berners-Lee]] first called the '''WorldWideWeb''' (note the name's use of [[CamelCase]], subsequently discarded) in 1990.<ref name="proposal">Berners-Lee, Tim & Robert Cailliau. 1990. [http://www.w3.org/Proposal.html WorldWideWeb: Proposal for a HyperText Project]. W3.org. Retrieved October 13, 2007.</ref>
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The underlying ideas of the Web can be traced as far back as 1980, when, at [[CERN]] in [[Switzerland]], [[ Sir Tim Berners-Lee]] built [[ENQUIRE]] (a reference to ''[[Enquire Within Upon Everything]]'', a book he recalled from his youth). While it was rather different from the system in use today, it contained many of the same core ideas (and even some of the ideas of Berners-Lee's next project after the World Wide Web, the [[Semantic Web]]).
  
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==Caching==
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In March 1989, Berners-Lee wrote a proposal<ref>''[http://www.w3.org/History/1989/proposal.html Information Management: A Proposal]''</ref> which referenced ENQUIRE and described a more elaborate information management system. With help from [[Robert Cailliau]], he published a more formal proposal for the World Wide Web on [[November 12]], [[1990]].<ref>[http://www.w3.org/Proposal Proposal for the World Wide Web]</ref> The proposal was modeled after EBT's (Electronic Book Technology, a spin-off from the
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If the user returns to a page fairly soon, it is likely that the data will not be retrieved from the source Web server, as above, again. By default, browsers [[cache]] all web resources on the local hard drive. An [[HTTP]] request will be sent by the browser that asks for the data ''only if it has been updated since the last download''. If it has not, the cached version will be reused in the rendering step.
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Institute for Research in Information and Scholarship at Brown University) Dynatext SGML reader that CERN had licensed. The [[Dynatext]] system, however technically advanced (a key player in the extension of SGML ISO 8879:1986 to Hypermedia within [[HyTime]]) was considered too expensive and with an inappropriate licensing policy for general HEP (High Energy Physics) community use: a fee for each document and each time a document was charged.
  
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This is particularly valuable in reducing the amount of Web traffic on the Internet. The decision about expiration is made independently for each resource (image, [[Cascading Style Sheets|stylesheet]], [[JavaScript]] file etc., as well as for the HTML itself). Thus even on sites with highly dynamic content, many of the basic resources are only supplied once per session or less.  It is worth it for any Web site designer to collect all the CSS and JavaScript into a few site-wide files so that they can be downloaded into users' caches and reduce page download times and demands on the server.
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A [[NeXTcube]] was used by Berners-Lee as the world's first [[Web server]] and also to write the first [[Web browser]], [[WorldWideWeb]], in 1990. By Christmas 1990, Berners-Lee had built all the tools necessary for a working Web:<ref>[http://www.w3.org/People/Berners-Lee/WorldWideWeb Tim Berners-Lee: WorldWideWeb, the first Web client<!-- Bot generated title —>]</ref> the [[WorldWideWeb|first Web browser]] (which was a Web editor as well), the first Web server, and the first Web pages<ref>[http://www.w3.org/History/19921103-hypertext/hypertext/WWW/TheProject.html First Web pages]</ref> which described the project itself.
  
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There are other components of the Internet that can cache Web content. The most common in practice are often built into corporate and academic [[Firewall (networking)|firewalls]] where they cache web resources requested by one user for the benefit of all. Some [[search engines]] such as [[Google]] or [[Yahoo!]] also store cached content from Web sites.
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On [[August 6]], [[1991]], he posted a short summary of the World Wide Web project on the <tt>alt.hypertext</tt> [[newsgroup]].<ref>[http://groups.google.com/group/alt.hypertext/msg/395f282a67a1916c Short summary of the World Wide Web project]</ref> This date also marked the debut of the Web as a publicly available service on the Internet.
  
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Apart from the facilities built into Web servers that can ascertain when physical files have been updated, it is possible for designers of dynamically generated web pages to control the HTTP headers sent back to requesting users, so that pages are not cached when they should not be — for example Internet banking and news pages.
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The first server outside of Europe was created at [[SLAC]] in December 1991 <ref>[http://www.slac.stanford.edu/history/earlyweb/history.shtml The Early World Wide Web at SLAC: Early Chronology and Documents<!-- Bot generated title —>]</ref>.
  
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This helps with understanding the difference between the HTTP 'GET' and 'POST' verbs - data requested with a GET may be cached, if other conditions are met, whereas data obtained after POSTing information to the server usually will not.
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The crucial underlying concept of [[hypertext]] originated with older projects from the 1960s, such as the Hypertext Editing System (HES) at Brown University--- among others [[Ted Nelson]] and [[Andries van Dam]]--- [[Ted Nelson]]'s [[Project Xanadu]] and [[Douglas Engelbart]]'s [[NLS (computer system)|oN-Line System]] (NLS). Both Nelson and Engelbart were in turn inspired by [[Vannevar Bush]]'s [[microfilm]]-based "[[memex]]," which was described in the 1945 essay "[[As We May Think]]".
  
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==History==
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Berners-Lee's breakthrough was to marry hypertext to the Internet. In his book ''Weaving The Web'', he explains that he had repeatedly suggested that a marriage between the two technologies was possible to members of ''both'' technical communities, but when no one took up his invitation, he finally tackled the project himself. In the process, he developed a system of globally unique identifiers for resources on the Web and elsewhere: the [[Uniform Resource Identifier]].
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{{main|History of the World Wide Web}}
 
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{{seealso|History of the Internet}} - [http://info.cern.ch/ CERN, Where the Web Was "WWW" born]
 
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[[Image:Premier_serveur_Web.jpeg|thumb|right|250px|This NeXTcube used by [[Tim Berners-Lee]] at CERN became the first Web server.]]
 
  
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The underlying ideas of the Web can be traced as far back as 1980, when, at [[CERN]] in [[Switzerland]], the Englishman [[Tim Berners-Lee]] built [[ENQUIRE]] (referring to ''[[Enquire Within Upon Everything]]'', a book he recalled from his youth). While it was rather different from the Web in use today, it contained many of the same core ideas (and even some of the ideas of Berners-Lee's next project after the WWW, the [[Semantic Web]]).  
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The World Wide Web had a number of differences from other hypertext systems that were then available. The Web required only unidirectional links rather than bidirectional ones. This made it possible for someone to link to another resource without action by the owner of that resource. It also significantly reduced the difficulty of implementing Web servers and browsers (in comparison to earlier systems), but in turn presented the chronic problem of [[link rot]]. Unlike predecessors such as [[HyperCard]], the World Wide Web was non-proprietary, making it possible to develop servers and clients independently and to add extensions without licensing restrictions.
  
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In March 1989, Tim Berners-Lee wrote a proposal<ref>Berners-Lee, Tim. 1990. [http://www.w3.org/History/1989/proposal.html Information Management: A Proposal]. W3.org. Retrieved October 13, 2007.</ref>, which referenced ENQUIRE and described a more elaborate information management system. With help from [[Robert Cailliau]], he published a more formal proposal for the World Wide Web<ref name="proposal"/> on November 12, 1990.  
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On [[April 30]], [[1993]], [[CERN]] announced<ref>[http://tenyears-www.web.cern.ch/tenyears-www/Welcome.html Ten Years Public Domain for the Original Web Software]</ref> that the World Wide Web would be free to anyone, with no fees due. Coming two months after the announcement that the [[Gopher (protocol)#Decline|Gopher]] protocol was no longer free to use, this produced a rapid shift away from Gopher and towards the Web. An early popular Web browser was [[ViolaWWW]], which was based upon [[HyperCard]].
  
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A [[NeXTcube]] was used by Berners-Lee as the world's first [[web server]] and also to write the first [[web browser]], [[WorldWideWeb]] in 1990. By Christmas 1990, Berners-Lee had built all the tools necessary for a working Web:<ref>Brenners-Lee, Tim. [http://www.w3.org/People/Berners-Lee/WorldWideWeb The WorldWideWeb browser]. W3.org. Retrieved October 13, 2007.</ref> the first Web browser (which was a Web editor as well), the first Web server and the first Web pages<ref>[http://www.w3.org/History/19921103-hypertext/hypertext/WWW/TheProject.html first Web pages]. W3.org. Retrieved October 13, 2007.</ref> which described the project itself.
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Scholars generally agree, however, that the [[Mosaic (web browser)#Importance of Mosaic|turning point]] for the World Wide Web began with the introduction<ref>[http://www.livinginternet.com/w/wi_mosaic.htm Mosaic Web Browser History - NCSA, Marc Andreessen, Eric Bina<!-- Bot generated title —>]</ref> of the [[Mosaic (web browser)|Mosaic]] Web browser<ref>[http://www.totic.org/nscp/demodoc/demo.html NCSA Mosaic - September 10, 1993 Demo<!-- Bot generated title —>]</ref> in 1993, a graphical browser developed by a team at the [[National Center for Supercomputing Applications]] at the [[University of Illinois at Urbana-Champaign]] (NCSA-UIUC), led by [[Marc Andreessen]]. Funding for Mosaic came from the ''High-Performance Computing and Communications Initiative'', a funding program initiated by the ''[[High Performance Computing and Communication Act of 1991]]'', one of [[Al Gore and information technology|several computing developments]] initiated by Senator [[Al Gore]].<ref>[http://www.cs.washington.edu/homes/lazowska/faculty.lecture/innovation/gore.html Vice President Al Gore's ENIAC Anniversary Speech<!-- Bot generated title —>]</ref> Prior to the release of Mosaic, graphics were not commonly mixed with text in Web pages, and its popularity was less than older protocols in use over the Internet, such as [[Gopher (protocol)|Gopher]] and [[Wide Area Information Servers]] (WAIS). Mosaic's graphical user interface allowed the Web to become, by far, the most popular Internet protocol.
  
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On August 6, 1991, he posted a short summary of the World Wide Web project on the <tt>alt.hypertext</tt> [[newsgroup]]<ref>[http://groups.google.com/groups?selm=6487%40cernvax.cern.ch short summary of the World Wide Web project]. Google Groups. Retrieved October 13, 2007.</ref>. This date also marked the debut of the Web as a publicly available service on the Internet.
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The World Wide Web Consortium (W3C) was founded by Tim Berners-Lee after he left the European Organization for Nuclear Research ([[CERN]]) in October, 1994. It was founded at the [[Massachusetts Institute of Technology]] Laboratory for Computer Science (MIT/LCS) with support from the [[Defense Advanced Research Projects Agency]] (DARPA)—which had pioneered the [[Internet]]—and the [[European Commission]].
  
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The crucial underlying concept of [[hypertext]] originated with older projects from the 1960s, such as [[Ted Nelson]]'s [[Project Xanadu]] and [[Douglas Engelbart]]'s [[NLS (computer system)|oN-Line System]] (NLS).  Both Nelson and Engelbart were in turn inspired by [[Vannevar Bush]]'s [[microfilm]]-based "[[memex]]," which was described in the 1945 essay "[[As We May Think]]." 
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==Standards==
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{{Main|Web standards}}
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Berners-Lee's breakthrough was to marry hypertext to the Internet. In his book ''Weaving The Web,'' he explains that he had repeatedly suggested that a marriage between the two technologies was possible to members of ''both'' technical communities, but when no one took up his invitation, he finally tackled the project himself. In the process, he developed a system of globally unique identifiers for resources on the Web and elsewhere: the [[Uniform Resource Identifier]].
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Many formal standards and other technical specifications define the operation of different aspects of the World Wide Web, the Internet, and computer information exchange. Many of the documents are the work of the [[World Wide Web Consortium]] (W3C), headed by Berners-Lee, but some are produced by the [[Internet Engineering Task Force]] (IETF) and other organizations.
  
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The World Wide Web had a number of differences from other hypertext systems that were then available:
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Usually, when Web standards are discussed, the following publications are seen as foundational:
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*The WWW required only unidirectional links rather than bidirectional ones. This made it possible for someone to link to another resource without action by the owner of that resource. It also significantly reduced the difficulty of implementing Web servers and browsers (in comparison to earlier systems), but in turn presented the chronic problem of [[link rot]].
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*Recommendations for [[markup languages]], especially [[HTML]] and [[XHTML]], from the W3C. These define the structure and interpretation of [[hypertext]] documents.
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*Unlike predecessors such as [[HyperCard]], the World Wide Web was non-proprietary, making it possible to develop servers and clients independently and to add extensions without licensing restrictions.
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*Recommendations for [[stylesheets]], especially [[Cascading Style Sheets|CSS]], from the W3C.
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*Standards for [[ECMAScript]] (usually in the form of [[JavaScript]]), from [[Ecma International]].
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*Recommendations for the [[Document Object Model]], from W3C.
  
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On April 30, 1993, [[CERN]] announced<ref>[http://intranet.cern.ch/Chronological/Announcements/CERNAnnouncements/2003/04-30TenYearsWWW/Welcome.html Ten Years Public Domain for the Original Web Software]. CERN. Retrieved October 13, 2007.</ref> that the World Wide Web would be free to anyone, with no fees due. Coming two months after the announcement that [[Gopher (protocol)#Decline|gopher]] was no longer free to use, this produced a rapid shift away from gopher and towards the Web. An early popular Web browser was [[ViolaWWW]] which was based upon [[HyperCard]].  
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Additional publications provide definitions of other essential technologies for the World Wide Web, including, but not limited to, the following:
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*''Uniform Resource Identifier'' ([[Uniform Resource Identifier|URI]]), which is a universal system for referencing resources on the Internet, such as hypertext documents and images. URIs, often called URLs, are defined by the IETF's RFC 3986 / STD 66: ''Uniform Resource Identifier (URI): Generic Syntax'', as well as its predecessors and numerous [[URI scheme]]-defining [[Request For Comments|RFCs]];
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*''HyperText Transfer Protocol (HTTP)'', especially as defined by RFC 2616: ''HTTP/1.1'' and RFC 2617: ''HTTP Authentication'', which specify how the browser and server authenticate each other.
  
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Scholars generally agree, however, that [[Mosaic (web browser)#Importance of Mosaic|the turning point for the World Wide Web began with the introduction]]<ref>[http://www.livinginternet.com/w/wi_mosaic.htm Mosaic — The First Global Web Browser]. Livinginternet.com. Retrieved October 13, 2007.</ref> of the [[Mosaic (web browser)|Mosaic]] web browser<ref>[http://www.totic.org/nscp/demodoc/demo.html NCSA Mosaic — September 10, 1993 Demo]. Totic.org. Retrieved October 13, 2007.</ref> in 1993, a graphical browser developed by a team at the [[National Center for Supercomputing Applications]] at the [[University of Illinois at Urbana-Champaign]] (NCSA-UIUC), led by [[Marc Andreessen]]. Funding for Mosaic came from the ''High-Performance Computing and Communications Initiative'', a funding program initiated by then-Senator [[Al Gore]]'s ''[[High Performance Computing and Communication Act of 1991]]'', also known as the ''[[Gore Bill]]''.<ref>Gore, Al. 1996. [http://www.cs.washington.edu/homes/lazowska/faculty.lecture/innovation/gore.html The Technology Challenge: How Can America Spark Private Innovation?]. CS.Washington.edu. Retrieved October 13, 2007.</ref>  Prior to the release of Mosaic, graphics were not commonly mixed with text in Web pages and its popularity was less than older protocols in use over the Internet, such as [[Gopher (protocol)|Gopher protocol]] and [[Wide area information server]]. Mosaic's graphical user interface allowed the Web to become by far the most popular Internet protocol.
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==Privacy==
  
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==Web standards==
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"We are left with the alarming question as to whether privacy should be put before global security." wrote Abhilash Sonwane of [[Cyberoam]].<ref>{{cite news|author=Sonwane, Abhilash|title=The cost of online anonymity|url=http://www.virusbtn.com/virusbulletin/archive/2008/10/vb200810-comment|date=October 2008|publisher=(preview via virusbtn.com) Virus Bulletin|accessdate=2008-09-26}}</ref> Among services paid for by advertising, [[Yahoo!]] could collect the most data about commercial Web users, about 2,500 bits of information per month about each typical user of its site and its affiliated advertising network sites. Yahoo! was followed by [[MySpace]] with about half that potential and then by [[AOL]]-[[TimeWarner]], [[Google]], [[Facebook]], [[Microsoft]], and [[eBay]].<ref>{{cite news|author=Story, Louise and comScore|title=They Know More Than You Think|url=http://www.nytimes.com/imagepages/2008/03/10/technology/20080310_PRIVACY_GRAPHIC.html|format=JPEG|date=[[March 10]], [[2008]]}} in {{cite news|author=Story, Louise|title=To Aim Ads, Web Is Keeping Closer Eye on You|url=http://www.nytimes.com/2008/03/10/technology/10privacy.html|work=The New York Times|publisher=The New York Times Company|date=[[March 10]], [[2008]]|accessdate=2008-03-09}}</ref> About 27% of websites operated outside <code>.com</code> addresses.<ref name=NI />
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At its core, the Web is made up of three standards:
 
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*the ''Uniform Resource Identifier'' ([[Uniform Resource Identifier|URI]]), which is a universal system for referencing resources on the Web, such as Web pages;
 
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*the ''HyperText Transfer Protocol'' ([[HTTP]]), which specifies how the browser and server communicate with each other; and
 
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*the ''HyperText Markup Language'' ([[HTML]]), used to define the structure and content of [[hypertext]] documents.
 
  
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Berners-Lee now heads the [[World Wide Web Consortium]] (W3C), which develops and maintains these and other standards that enable computers on the Web to effectively store and communicate different forms of information.
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==Security==
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The Web has become criminals' preferred pathway for spreading [[malware]]. Cybercrime carried out on the Web can include [[identity theft]], fraud, espionage and intelligence gathering.<ref name=Ben-Itzhak /> Web-based vulnerabilities now outnumber traditional computer security concerns,<ref>XSS vulnerabilties outnumbered buffer overflows, in {{cite web|author=Christey, Steve and Martin, Robert A.|title=Vulnerability Type Distributions in CVE (version 1.1)|url=http://cwe.mitre.org/documents/vuln-trends/index.html|date=[[May 22]], [[2007]]|publisher=MITRE Corporation|accessdate=2008-06-07}} During the second half of 2007, XSS outnumbered "traditional" vulnerabilities, in {{cite web|title=Symantec Internet Security Threat Report: Trends for July-December 2007 (Executive Summary)|publisher=Symantec Corp.|volume=XIII|pages=1–2|date=April 2008|url=http://eval.symantec.com/mktginfo/enterprise/white_papers/b-whitepaper_exec_summary_internet_security_threat_report_xiii_04-2008.en-us.pdf|format=PDF|accessdate=2008-05-11}}</ref> and as measured by [[Google]], about one in ten Web pages may contain malicious code.<ref>{{cite news|title=Google searches web's dark side|url=http://news.bbc.co.uk/2/hi/technology/6645895.stm|date=[[May 11]], [[2007]]|publisher=BBC News|accessdate=2008-04-26}}</ref> Most Web-based attacks take place on legitimate websites, and most, as measured by [[Sophos]], are hosted in the United States, China and Russia.<ref name=Sophos-Q1-2008>{{cite web|title=Security Threat Report|url=http://www.sophos.com/sophos/docs/eng/marketing_material/sophos-threat-report-Q108.pdf|format=PDF|date=Q1 2008|publisher=Sophos|accessdate=2008-04-24}}</ref>
  
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==Java and JavaScript==
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The most common of all malware threats is [[SQL injection]] attacks against websites.<ref>{{cite web|title=Security threat report|url=http://www.sophos.com/sophos/docs/eng/papers/sophos-security-report-jul08-srna.pdf|format=PDF|date=July 2008|publisher=Sophos|accessdate=2008-08-24}}</ref> Through HTML and URIs the Web was vulnerable to attacks like [[cross-site scripting]] (XSS) that came with the introduction of JavaScript<ref name=FGHR>{{cite book|author=Fogie, Seth, Jeremiah Grossman, Robert Hansen, and Anton Rager|title=Cross Site Scripting Attacks: XSS Exploits and Defense|pages=68–69, 127|publisher=Syngress, Elsevier Science & Technology|url=http://www.syngress.com/book_catalog//SAMPLE_1597491543.pdf|format=PDF|date=2007|isbn=1597491543|accessdate=2008-06-06}}</ref> and were exacerbated to some degree by Web 2.0 and Ajax [[web design]] that favors the use of scripts.<ref>{{cite web|author=O'Reilly, Tim|title=What Is Web 2.0|url=http://www.oreillynet.com/pub/a/oreilly/tim/news/2005/09/30/what-is-web-20.html|pages=4–5|date=[[September 30]], [[2005]]|publisher=O'Reilly Media|accessdate=2008-06-04}} and AJAX web applications can introduce security vulnerabilities like "client-side security controls, increased attack surfaces, and new possibilities for Cross-Site Scripting (XSS)", in {{cite journal|author=Ritchie, Paul|title=The security risks of AJAX/web 2.0 applications|url=http://www.infosecurity-magazine.com/research/Sep07_Ajax.pdf|format=PDF|date=March 2007|journal=Infosecurity|publisher=Elsevier|accessdate=2008-06-06}} which cites {{cite news|author=Hayre, Jaswinder S. and Kelath, Jayasankar|title=Ajax Security Basics|url=http://www.securityfocus.com/infocus/1868|publisher=SecurityFocus|date=[[June 22]], [[2006]]|accessdate=2008-06-06}}</ref> Today by one estimate, 70% of all websites are open to XSS attacks on their users.<ref>{{cite news|author=Berinato, Scott|title=Software Vulnerability Disclosure: The Chilling Effect|url=http://www.csoonline.com/article/221113|work=CSO|page=7|publisher=CXO Media|date=[[January 1]], [[2007]]|accessdate=2008-06-07}}</ref>
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A significant advance in Web technology was [[Sun Microsystems|Sun Microsystems']] [[Java Platform|Java platform]]. It enables Web pages to embed small programs (called [[applet]]s) directly into the view. These applets run on the end-user's computer, providing a richer user interface than simple web pages. Java client-side applets never gained the popularity that Sun had hoped for, for a variety of reasons including lack of integration with other content (applets were confined to small boxes within the rendered page) and the fact that many computers at the time were supplied to end users without a suitably installed [[Java Virtual Machine|JVM]], and so required a download by the user before applets would appear. [[Adobe Flash]] now performs many of the functions that were originally envisioned for Java applets including the playing of video content, animation and some rich [[Graphical user interface|UI]] features. [[Java (programming language)|Java]] itself has become more widely used as a platform and language for [[server-side]] and other programming.
 
  
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[[JavaScript]], on the other hand, is a [[Scripting programming language|scripting language]] that was initially developed for use within Web pages. The standardized version is [[ECMAScript]]. While its name is similar to Java, JavaScript was developed by [[Netscape Communications Corporation|Netscape]] and it has almost nothing to do with Java, apart from that, like Java, its syntax is derived from the [[C (programming language)|C programming language]]. In conjunction with a Web page's [[Document Object Model]], JavaScript has become a much more powerful technology than its creators originally envisioned. The manipulation of a page's Document Object Model after the page is delivered to the client has been called [[Dynamic HTML]] (DHTML), to emphasize a shift away from ''static'' HTML displays. 
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Proposed solutions vary to extremes. Large security vendors like [[McAfee]] already design governance and compliance suites to meet post-9/11 regulations,<ref>{{cite news|author=Prince, Brian|title=McAfee Governance, Risk and Compliance Business Unit|url=http://www.eweek.com/c/a/Security/McAfee-Governance-Risk-and-Compliance-Business-Unit/|work=eWEEK|publisher=Ziff Davis Enterprise Holdings|date=[[April 9]], [[2008]]|accessdate=2008-04-25}}</ref> and some, like [[Finjan]] have recommended active real-time inspection of code and all content regardless of its source.<ref name=Ben-Itzhak>{{cite news|author=Ben-Itzhak, Yuval|title=Infosecurity 2008 - New defence strategy in battle against e-crime|url=http://www.computerweekly.com/Articles/2008/04/18/230345/infosecurity-2008-new-defence-strategy-in-battle-against.htm|work=ComputerWeekly|publisher=Reed Business Information|date=[[April 18]], [[2008]]|accessdate=2008-04-20}}</ref> Some have argued that for enterprise to see security as a business opportunity rather than a cost center,<ref>{{cite news|author=Preston, Rob|title=Down To Business: It's Past Time To Elevate The Infosec Conversation|url=http://www.informationweek.com/news/security/client/showArticle.jhtml?articleID=207100989|work=InformationWeek|publisher=United Business Media|date=[[April 12]], [[2008]]|accessdate=2008-04-25}}</ref> "ubiquitous, always-on digital rights management" enforced in the infrastructure by a handful of organizations must replace the hundreds of companies that today secure data and networks.<ref>{{cite news|author=Claburn, Thomas|title=RSA's Coviello Predicts Security Consolidation|url=http://www.informationweek.com/news/security/showArticle.jhtml?articleID=197003826|work=InformationWeek|publisher=United Business Media|date=[[February 6]], [[2007]]|accessdate=2008-04-25}}</ref> [[Jonathan Zittrain]] has said users sharing responsibility for computing safety is far preferable to locking down the Internet.<ref>{{cite news|first=Carolyn|last= Duffy Marsan|title= How the iPhone is killing the 'Net|url= http://www.networkworld.com/news/2008/040908-zittrain.html|work= Network World|publisher= IDG|date= [[April 9]], [[2008]]|accessdate= 2008-04-17}}</ref>
  
−
In its simplest form, all the optional information and actions available on a JavaScripted Web page will have been downloaded when the page was first delivered. [[Ajax (programming)|Ajax]] ("Asynchronous JavaScript And XML") is a JavaScript-based technology that may have a significant effect on the development of the World Wide Web. Ajax provides a method whereby large or small parts ''within'' a Web page may be updated, using new information obtained over the network in response to user actions. This allows the page to be much more responsive, interactive and interesting, without the user having to wait for whole-page reloads. Ajax is seen as an important aspect of what is being called [[Web 2.0]]. Examples of Ajax techniques currently in use can be seen in [[Gmail]], [[Google Maps]] etc.
+
==Web Accessibility==
 +
{{Main|Web accessibility}}
  
−
==Sociological implications==
+
Many countries regulate [[web accessibility]] as a requirement for web sites.
  
−
The Web, as it stands today, has allowed global interpersonal exchange on a scale unprecedented in human history. People separated by vast distances, or even large amounts of time, can use the Web to exchange—or even mutually develop—their most intimate and extensive thoughts, or alternately their most casual attitudes and spirits. Emotional experiences, political ideas, cultural customs, musical idioms, business advice, artwork, photographs, literature, can all be shared and disseminated digitally with less individual investment than ever before in human history. Although the existence and use of the Web relies upon material technology, which comes with its own disadvantages, its information does not use physical resources in the way that libraries or the printing press have. Therefore, propagation of information via the Web (via the Internet, in turn) is not constrained by movement of physical volumes, or by manual or material copying of information. By virtue of being digital, the information of the Web can be searched more easily and efficiently than any library or physical volume, and vastly more quickly than a person could retrieve information about the world by way of physical travel or by way of mail, telephone, telegraph, or any other communicative medium.
+
==Java==
 +
A significant advance in Web technology was [[Sun Microsystems|Sun Microsystems']] [[Java platform]]. It enables Web pages to embed small programs (called [[applet]]s) directly into the view. These applets run on the end-user's computer, providing a richer user interface than simple Web pages. Java client-side applets never gained the popularity that Sun had hoped for a variety of reasons, including lack of integration with other content (applets were confined to small boxes within the rendered page) and the fact that many computers at the time were supplied to end users without a suitably installed [[Java Virtual Machine]], and so required a download by the user before applets would appear. [[Adobe Flash]] now performs many of the functions that were originally envisioned for Java applets, including the playing of video content, animation, and some rich [[Graphical user interface|GUI]] features. [[Java (programming language)|Java]] itself has become more widely used as a platform and language for [[server-side]] and other programming.
  
−
The Web is the most far-reaching and extensive medium of personal exchange to appear on Earth. It has probably allowed many of its users to interact with many more groups of people, dispersed around the planet in time and space, than is possible when limited by physical contact or even when limited by every other existing medium of communication combined.
+
==JavaScript==
 +
[[JavaScript]], on the other hand, is a [[Scripting programming language|scripting language]] that was initially developed for use within Web pages. The standardized version is [[ECMAScript]]. While its name is similar to Java, JavaScript was developed by [[Netscape Communications Corporation|Netscape]] and has very little to do with Java, although the syntax of both languages is derived from the [[C (programming language)|C]] programming language. In conjunction with a Web page's [[Document Object Model]] (DOM), JavaScript has become a much more powerful technology than its creators originally envisioned.{{Fact|date=August 2008}} The manipulation of a page's DOM after the page is delivered to the client has been called [[Dynamic HTML]] (DHTML), to emphasize a shift away from ''static'' HTML displays.
  
−
Because the Web is global in scale, some have suggested that it will nurture mutual understanding on a global scale. By definition or by necessity, the Web has such a massive potential for social exchange, it has the potential to nurture empathy and symbiosis, but it also has the potential to incite belligerence on a global scale, or even to empower demagogues and repressive regimes in ways that were historically impossible to achieve previously.
+
In simple cases, all the optional information and actions available on a JavaScript-enhanced Web page will have been downloaded when the page was first delivered. [[Ajax (programming)|Ajax]] ("Asynchronous JavaScript and XML") is a group of interrelated web development techniques used for creating interactive web applications that provide a method whereby parts ''within'' a Web page may be updated, using new information obtained over the network at a later time in response to user actions. This allows the page to be more responsive, interactive and interesting, without the user having to wait for whole-page reloads. Ajax is seen as an important aspect of what is being called [[Web 2.0]]. Examples of Ajax techniques currently in use can be seen in [[Gmail]], [[Google Maps]], and other dynamic Web applications.
  
 
==Publishing Web pages==
 
==Publishing Web pages==
−
The Web is available to individuals outside [[mass media]]. In order to "publish" a Web page, one does not have to go through a [[publisher]] or other media institution, and potential readers could be found in all corners of the globe.
+
Web page production is available to individuals outside the [[mass media]]. In order to publish a Web page, one does not have to go through a [[publisher]] or other media institution, and potential readers could be found in all corners of the globe.
  
−
Unlike [[book]]s and documents, hypertext does not need to have a linear order from beginning to end. It is not necessarily broken down into the hierarchy of chapters, sections, subsections, etc.
+
Many different kinds of information are available on the Web, and for those who wish to know other societies, cultures, and peoples, it has become easier.
  
−
Many different kinds of information are now available on the Web, and for those who wish to know other societies, their cultures and peoples, it has become easier. When traveling in a foreign country or a remote town, one might be able to find some information about the place on the Web, especially if the place is in one of the developed countries. Local newspapers, government publications, and other materials are easier to access, and therefore the variety of information obtainable with the same effort may be said to have increased, for the users of the Internet.  
+
The increased opportunity to publish materials is observable in the countless personal and social networking pages, as well as sites by families, small shops, etc., facilitated by the emergence of free [[Web hosting]] services.
  
−
Although some Web sites are available in multiple languages, many are in the local language only. Additionally, not all software supports all special characters, and [[Bi-directional text|RTL]] languages. These factors would challenge the notion that the World Wide Web will bring a unity to the world.
+
==Statistics==
−
 
+
According to a 2001 study, there were massively more than 550 billion documents on the Web, mostly in the invisible Web, or [[deep Web]].<ref>[http://www.brightplanet.com/resources/details/deepweb.html The 'Deep' Web: Surfacing Hidden Value]</ref> A 2002 survey of 2,024 million Web pages<ref>[http://www.netz-tipp.de/languages.html Distribution of languages on the Internet<!-- Bot generated title —>]</ref> determined that by far the most Web content was in English: 56.4%; next were pages in German (7.7%), French (5.6%), and Japanese (4.9%). A more recent study, which used Web searches in 75 different languages to sample the Web, determined that there were over 11.5 billion Web pages in the [[Surface Web|publicly indexable Web]] as of the end of January 2005.<ref>[http://www.cs.uiowa.edu/~asignori/web-size/ Indexable Web Size<!-- Bot generated title —>]</ref> As of June 2008, the indexable web contains at least 63 billion pages.<ref>[http://www.worldwidewebsize.com/ The size of the World Wide Web]</ref> On July 25, 2008, Google software engineers Jesse Alpert and Nissan Hajaj announced that [[Google Search]] had discovered one trillion unique URLs.<ref>{{cite web |url=http://googleblog.blogspot.com/2008/07/we-knew-web-was-big.html |title=We knew the web was big... |accessdate= |last=Alpert |first=Jesse |coauthors=Hajaj, Nissan |date=2008-07-25 |work=The Official Google Blog |publisher=}}</ref>
−
The increased opportunity to publish materials is certainly observable in the countless personal pages, as well as pages by families, small shops, etc., facilitated by the emergence of free [[Web hosting]] services.
 
  
−
==Statistics==
+
Over 100.1 million websites operated as of March 2008.<ref name=NI>{{cite web|title=Domain Counts & Internet Statistics|url=http://www.domaintools.com/internet-statistics/|publisher=Name Intelligence|accessdate=2008-03-11}}</ref> Of these 74% were commercial or other sites operating in the <code>.com</code> [[generic top-level domain]].<ref name=NI />  
−
According to a 2001 study,<ref>[http://www.brightplanet.com/technology/deepweb.asp The 'Deep' Web: Surfacing Hidden Value]. Bright Planet. Retrieved October 13, 2007.</ref> there were more than 550 million documents on the Web, mostly in the "[[Deep web|invisible Web]]." A 2002 survey of 2,024 million Web pages<ref>[http://www.netz-tipp.de/languages.html Internet Statistics: Distribution of languages on the Internet]. Netz-Tipp. Retrieved October 13, 2007.</ref> determined that by far the most Web content was in English: 56.4%; next were pages in German (7.7%), French (5.6%) and Japanese (4.9%). A more recent study which used web searches in 75 different languages to sample the Web determined that there were over 11.5 billion web pages in the [[Surface Web|publicly indexable Web]] as of the end of  January 2005.<ref>Gulli, Antonio, Alessio Signorini. [http://www.cs.uiowa.edu/~asignori/web-size/ The Indexable Web is more than 11.5 billion pages]. CS.UIowa.com. Retrieved October 13, 2007.</ref>
 
  
 
==Speed issues==
 
==Speed issues==
−
Frustration over [[congestion]] issues in the [[Internet]] infrastructure and the high [[Latency (engineering)|latency]] that results in slow browsing has led to an alternative name for the World Wide Web: the ''World Wide Wait''. Speeding up the Internet is an ongoing discussion over the use of [[peering]] and [[Quality of service|QoS]] technologies. Other solutions to reduce the World Wide Wait can be found on [http://www.w3.org/Protocols/NL-PerfNote.html W3C].
+
Frustration over [[congestion]] issues in the [[Internet]] infrastructure and the high [[Latency (engineering)|latency]] that results in slow browsing has led to an alternative, pejorative name for the World Wide Web: the ''World Wide Wait''.{{Fact|date=August 2008}} Speeding up the Internet is an ongoing discussion over the use of [[peering]] and [[Quality of service|QoS]] technologies. Other solutions to reduce the World Wide Wait can be found on [http://www.w3.org/Protocols/NL-PerfNote.html W3C].
  
−
Standard [[guideline]]s for ideal Web response times are (Nielsen 1999, page 42):
+
Standard [[guideline]]s for ideal Web response times are:<ref>Nielsen 1999, `Designing Web Usability', page 42</ref>
−
* 0.1 second (one tenth of a second). Ideal response time. The user doesn't sense any interruption.
+
*0.1 second (one tenth of a second). Ideal response time. The user doesn't sense any interruption.
−
* 1 second. Highest acceptable response time. Download times above 1 second interrupt the user experience.
+
*1 second. Highest acceptable response time. Download times above 1 second interrupt the user experience.
−
* 10 seconds. Unacceptable response time. The user experience is interrupted and the user is likely to leave the site or system.  
+
*10 seconds. Unacceptable response time. The user experience is interrupted and the user is likely to leave the site or system.
 
These numbers are useful for planning server capacity.
 
These numbers are useful for planning server capacity.
 +
 +
==Caching==
 +
If a user revisits a Web page after only a short interval, the page data may not need to be re-obtained from the source Web server. Almost all Web browsers [[cache]] recently-obtained data, usually on the local hard drive. HTTP requests sent by a browser will usually only ask for data that has changed since the last download. If the locally-cached data is still current, it will be reused.
 +
 +
Caching helps reduce the amount of Web traffic on the Internet. The decision about expiration is made independently for each downloaded file, whether image, [[Cascading Style Sheets|stylesheet]], [[JavaScript]], HTML, or whatever other content the site may provide. Thus even on sites with highly dynamic content, many of the basic resources only need to be refreshed occasionally. Web site designers find it worthwhile to collate resources such as CSS data and JavaScript into a few site-wide files so that they can be cached efficiently. This helps reduce page download times and lowers demands on the Web server.
 +
 +
There are other components of the Internet that can cache Web content. Corporate and academic [[Firewall (networking)|firewalls]] often cache Web resources requested by one user for the benefit of all. (See also [[Web proxy#Caching proxy server|Caching proxy server]].) Some [[search engines]], such as [[Google]] or [[Yahoo!]], also store cached content from websites.
 +
 +
Apart from the facilities built into Web servers that can determine when files have been updated and so need to be re-sent, designers of dynamically-generated Web pages can control the HTTP headers sent back to requesting users, so that transient or sensitive pages are not cached. [[Online banking|Internet banking]] and news sites frequently use this facility.
 +
 +
Data requested with an [[Hypertext Transfer Protocol|HTTP]] 'GET' is likely to be cached if other conditions are met; data obtained in response to a 'POST' is assumed to depend on the data that was POSTed and so is not cached.
  
 
==Link rot and Web archival==
 
==Link rot and Web archival==
−
{{main|link rot}}
+
{{main|Link rot}}
−
Over time, many Web resources pointed to by hyperlinks disappear, relocate, or are replaced with different content. This phenomenon is referred to in some circles as "[[link rot]]" and the hyperlinks affected by it are often called "[[dead link]]s."
+
Over time, many Web resources pointed to by hyperlinks disappear, relocate, or are replaced with different content. This phenomenon is referred to in some circles as "[[link rot]]" and the hyperlinks affected by it are often called "[[dead link]]s".
  
−
The ephemeral nature of the Web has prompted many efforts to archive the Web. The [[Internet Archive]] is one of the most well-known efforts; they have been archiving the Web since 1996.
+
The ephemeral nature of the Web has prompted many efforts to archive Web sites. The [[Internet Archive]] is one of the most well-known efforts; it has been active since 1996.
  
 
==Academic conferences==
 
==Academic conferences==
−
The major academic event covering the WWW is the World Wide Web series of conferences, promoted by [http://www.iw3c2.org IW3C2]. There is a [http://www.iw3c2.org/conferences/ list] with links to all conferences in the series.
+
The major academic event covering the Web is the [[World Wide Web Conference]], promoted by [[IW3C2]].
  
 
==WWW prefix in Web addresses==
 
==WWW prefix in Web addresses==
−
"www" is commonly found at the beginning of [[Web address]]es because of the long-standing practice of naming Internet hosts (servers) according to the services they provide. So for example, the host name for a [[Web server]] is often "www"; for an [[FTP server]], "ftp"; and for a [[USENET]] [[news server]], "news" or "nntp" (after the news protocol [[NNTP]]). These host names appear as [[Domain name system|DNS]] [[subdomain]] names, as in "www.example.com."
+
The letters "www" are commonly found at the beginning of [[Web address]]es because of the long-standing practice of naming Internet hosts (servers) according to the services they provide. So for example, the host name for a [[Web server]] is often "www"; for an [[FTP server]], "ftp"; and for a [[USENET]] [[news server]], "news" or "nntp" (after the news protocol [[NNTP]]). These host names appear as [[Domain name system|DNS]] [[subdomain]] names, as in "www.example.com".
  
−
This use of such prefixes is not required by any technical standard; indeed, the first Web server was at "nxoc01.cern.ch"<ref>[http://www.w3.org/People/Berners-Lee/FAQ.html Frequently asked questions]. W3.org. Retrieved October 13, 2007.</ref> and even today many Web sites exist without a "www" prefix. The "www" prefix has no meaning in the way the main website is shown. The "www" prefix is simply one choice for a Web site's subdomain name.
+
This use of such prefixes is not required by any technical standard; indeed, the first Web server was at "nxoc01.cern.ch",<ref>[http://www.w3.org/People/Berners-Lee/FAQ.html Frequently asked questions by the Press - Tim Berners-Lee<!-- Bot generated title —>]</ref> and even today many Web sites exist without a "www" prefix. The "www" prefix has no meaning in the way the main Web site is shown. The "www" prefix is simply one choice for a Web site's host name.
  
−
Some Web browsers will automatically try adding "www." to the beginning, and possibly ".com" to the end, of typed URLs if no host is found without them. [[Internet Explorer]], [[Mozilla Firefox]] and [[Opera (Internet suite)|Opera]] will also prefix "<nowiki>http://www.</nowiki>" and append ".com" to the address bar contents if the Control and Enter keys are pressed simultaneously. For example, entering "example" in the address bar and then pressing either just Enter or Control+Enter will usually resolve to <nowiki>"http://www.example.com"</nowiki>, depending on the exact browser version and its settings.
+
However, some website addresses require the www. prefix, and if typed without one, won't work; there are also some which must be typed ''without'' the prefix.  
  
−
== Pronunciation of "www" ==
+
Some Web browsers will automatically try adding "www." to the beginning, and possibly ".com" to the end, of typed URLs if no host is found without them. All major web browser will also prefix "<nowiki>http://www.</nowiki>" and append ".com" to the address bar contents if the Control and Enter keys are pressed simultaneously. For example, entering "example" in the address bar and then pressing either just Enter or Control+Enter will usually resolve to "<nowiki>http://www.example.com</nowiki>", depending on the exact browser version and its settings.
−
In [[English language|English]], WWW is the longest possible [[three-letter acronym]] (TLA) to pronounce, requiring nine [[syllable]]s. The late [[Douglas Adams]] once quipped:
 
−
{{Quotation|The World Wide Web is the only thing I know of whose shortened form takes three times longer to say than its long form.|Douglas Adams|[[The Independent|The Independent on Sunday]], 1999}}
 
  
−
To pronounce: "double you double you double you"
+
===Pronunciation of "www"===
 +
{{main|Pronunciation of "www"}}
 +
In [[English language|English]], "www" is pronounced '''"double-you double-you double-you"'''. It is sometimes shortened to '''"triple-double-you"''' or '''"dub, dub, dub".'''
  
−
In practice it is sometimes shortened, in English usage, to "triple double-you," run together as "DubaDubaDub-u.," or even just "Dub-Dub-Dub." In other languages, "www" may be pronounced like "veh-veh-veh." The early "w³" abbreviation is now defunct.
+
The English writer [[Douglas Adams]] once quipped:
 +
{{Quotation|The World Wide Web is the only thing I know of whose shortened form takes three times longer to say than what it's short for.|Douglas Adams|[[The Independent|The Independent on Sunday]], 1999}}
  
−
In [[Chinese language|Chinese]], the World Wide Web is commonly translated to ''wàn wéi wǎng'' ({{lang|zh|万维网}}), which satisfies "www" and literally means "ten-thousand dimensional net".{{Fact|date=March 2007}}
+
It is also interesting that in Mandarin [[Chinese language|Chinese]], "World Wide Web" is commonly translated via a [[phono-semantic matching]] to ''wàn wéi wǎng'' ({{lang|zh|[[wikt:万维网|万维网]]}}), which satisfies "www" and literally means "myriad dimensional net",<ref>See [[CEDICT]] or the [http://www.mdbg.net/chindict/chindict.php?page=translate&trst=0&trqs=World+Wide+Web&trlang=&wddmtm=0 MDBG Chinese-English Dictionary].</ref> a translation that very appropriately reflects the design concept and proliferation of the World Wide Web.
−
 
 
−
==Standards==
 
−
{{Main|W3C}}
 
−
The following is a cursory list of the documents that define the World Wide Web's three core standards:
 
−
 
 
−
*'''Uniform Resource Locators (URL)'''
 
−
**RFC 1738, Uniform Resource Locators (URL) (December 1994)
 
−
**RFC 3986, Uniform Resource Identifier (URI): Generic Syntax (January 2005)
 
−
*'''HyperText Transfer Protocol (HTTP)'''
 
−
**RFC 1945, HTTP/1.0 specification (May 1996)
 
−
**RFC 2616, HTTP/1.1 specification (June 1999)
 
−
**RFC 2617, HTTP Authentication
 
−
**[http://purl.org/NET/http-errata HTTP/1.1 specification errata]
 
−
*'''HyperText Markup Language (HTML)'''
 
−
**[http://www.w3.org/MarkUp/draft-ietf-iiir-html-01.txt Internet Draft, HTML version 1]
 
−
**RFC 1866, HTML version 2.0
 
−
**[http://www.w3.org/TR/REC-html32 HTML 3.2 Reference Specification]
 
−
**[http://www.w3.org/TR/html4/ HTML 4.01 Specification]
 
−
**[http://www.w3.org/TR/html/ Extensible HTML (XHTML) Specification]
 
−
 
 
−
==See also==
 
  
 +
== See also ==
 +
<div style="-moz-column-count:3; -webkit-column-count:3; column-count:3;">
 +
*[[Amaya (web browser)|Amaya Web browser]]
 
*[[Deep web]]
 
*[[Deep web]]
−
*[[First image on the Web]]
+
*[[List of websites]]
−
*[[Search engine]]
+
*[[Web search engine|Search engine]]
 
*[[Streaming media]]
 
*[[Streaming media]]
 +
*[[Web 1.0]]
 
*[[Web 2.0]]
 
*[[Web 2.0]]
 +
*[[Web 3.0]]
 +
*[[Web accessibility]]
 +
*[[Web archiving]]
 
*[[Web directory]]
 
*[[Web directory]]
 
*[[Web operating system]]
 
*[[Web operating system]]
 +
*[[Web science]]
 
*[[Web services]]
 
*[[Web services]]
−
*[[Web science]]
 
 
*[[Webology]]
 
*[[Webology]]
 
*[[Website]]
 
*[[Website]]
 
*[[Website architecture]]
 
*[[Website architecture]]
 +
*[[Internet]]
 +
</div>
  
−
== Notes ==
+
==Notes==
−
<references/>
+
{{reflist|2}}
  
 
==References==
 
==References==
−
 
+
*{{cite paper | author=Fielding, R.; Gettys, J.; Mogul, J.; Frystyk, H.; Masinter, L.; Leach, P.; Berners-Lee, T. | title=Hypertext Transfer Protocol — HTTP/1.1 | publisher=Information Sciences Institute | date=June 1999 | version=Request For Comments 2616 | url=ftp://ftp.isi.edu/in-notes/rfc2616.txt}}
−
*Gillies, James and Robert Cailliau. 2000. ''How the Web was Born: The Story of the World Wide Web''. New York, NY: Oxford University Press, USA. ISBN 0192862073.
+
*{{cite paper | author=Berners-Lee, Tim; Bray, Tim; Connolly, Dan; Cotton, Paul; Fielding, Roy; Jeckle, Mario; Lilley, Chris; Mendelsohn, Noah; Orchard, David; Walsh, Norman; Williams, Stuart | title=Architecture of the World Wide Web, Volume One | publisher=W3C | date=December 15, 2004 | version=Version 20041215 | url=http://www.w3.org/TR/webarch/}}
−
*Levy, Patricia. 2005. ''From the World Wide Web to September 11: The Early 1990s to 2001''. Chicago, IL: Raintree. ISBN 1844439682.
+
*{{cite web | author=Polo, Luciano | title=World Wide Web Technology Architecture: A Conceptual Analysis | publisher= | year=2003 | work=New Devices | url=http://newdevices.com/publicaciones/www/ | accessmonthday=July 31 | accessyear=2005 }}
−
*Berners-Lee, Tim. 2000. ''Weaving the Web: The Original Design and Ultimate Destiny of the World Wide Web''. New York, NY: HarperCollins Publishers. ISBN 006251587X.
 
−
*Fielding, R., J. Gettys, J. Mogul, H. Frystyk, L. Masinter, P. Leach, T. Berners-Lee. 1999. [ftp://ftp.isi.edu/in-notes/rfc2616.txtHypertext Transfer Protocol — HTTP/1.1]. Information Sciences Institute. Retrieved October 13, 2007.
 
−
*Berners-Lee, Tim; Tim Bray, Dan Connolly, Paul Cotton, Roy Fielding, Mario Jeckle, Chris Lilley, Noah Mendelsohn, David Orchard, Norman Walsh, Stuart Williams. 2004. [http://www.w3.org/TR/webarch/ Architecture of the World Wide Web, Volume One]. W3C. Retrieved October 13, 2007.
 
−
*Polo, Luciano. 2003. [http://newdevices.com/publicaciones/www/ World Wide Web Technology Architecture: A Conceptual Analysis]. New Devices. Retrieved October 13, 2007.
 
  
 
==External links==
 
==External links==
 +
{{wikibooks|Nets, Webs and the Information Infrastructure}}
 +
*[http://www.w3.org/History/19921103-hypertext/hypertext/WWW/ Early archive of the first Web site]
 +
*[http://www.mit.edu/people/mkgray/net/ Internet Statistics: Growth and Usage of the Web and the Internet]
 +
*[http://www.livinginternet.com/w/w.htm Living Internet] A comprehensive history of the Internet, including the World Wide Web.
 +
*[http://www2007.org/ Official WWW conference, 2007]
 +
*[http://www2006.org/ Official WWW conference, 2006]
 +
*[http://dmoz.org/Computers/Internet/Web_Design_and_Development/ Open Directory — Computers: Internet: Web Design and Development]
 +
* [http://www.semantic-systems-biology.org Semantic Systems Biology]
 +
*[http://www.tomandmaria.com/tom/Writing/ProtocolsForProfitDRAFT.pdf Thomas Haigh, "Protocols for Profit: Web and Email Technologies as Product and Infrastructure" in The Internet & American Business, eds. Ceruzzi & Aspray, MIT Press, 2008] Business & technological history of Web browsers, online preprint.
 +
*[http://www.informationweek.com/news/internet/showArticle.jhtml?articleID=199203958 What's The Greatest Web Software Ever Written?]
 +
*[http://www.w3.org/ World Wide Web Consortium]
 +
*[http://www.worldwidewebsize.com/ World Wide Web Size] Daily estimated size of the World Wide Web.
 +
*[http://www.w3c-at.de/wspolicy-pressrelease.php WsPolicy Pressrealease] (German)
 +
*[http://hydrogen.informatik.tu-cottbus.de/wiki/index.php/ Web Technologies Wiki]
  
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*[http://www.w3.org/History/19921103-hypertext/hypertext/WWW/ Early archive of the first web site]. Retrieved October 13, 2007.
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*[http://www.mit.edu/people/mkgray/net/ Internet Statistics: Growth and Usage of the Web and the Internet]. Retrieved October 13, 2007.
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*[http://www.worldwidewebsize.com World Wide Web Size] Daily estimated size of the World Wide Web. Retrieved October 13, 2007.
 
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*[http://relics.monkhq.com Relics of the Internet] Daily Internet Historical Finds. Dive into the past of the Net. Retrieved October 13, 2007.
 
  
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Revision as of 16:47, 10 November 2008

Portal World Wide Web Portal
"The World Wide Web" and "WWW" redirect here. For other uses, see Web and WWW (disambiguation). "Web surfing" redirects here. For the Web browser, see WorldWideWeb.
WWW's historic logo designed by Robert Cailliau

The World Wide Web (commonly shortened to the Web) is a system of interlinked hypertext documents accessed via the Internet. With a Web browser, one can view Web pages that may contain text, images, videos, and other multimedia and navigate between them using hyperlinks. The World Wide Web was created in 1989 by English scientist Tim Berners-Lee, working at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland, and released in 1992. Since then, Berners-Lee has played an active role in guiding the development of Web standards (such as the markup languages in which Web pages are composed), and in recent years has advocated his vision of a Semantic Web.

How it works

Viewing a Web page on the World Wide Web normally begins either by typing the URL of the page into a Web browser, or by following a hyperlink to that page or resource. The Web browser then initiates a series of communication messages, behind the scenes, in order to fetch and display it.

First, the server-name portion of the URL is resolved into an IP address using the global, distributed Internet database known as the domain name system, or DNS. This IP address is necessary to contact and send data packets to the Web server.

The browser then requests the resource by sending an HTTP request to the Web server at that particular address. In the case of a typical Web page, the HTML text of the page is requested first and parsed immediately by the Web browser, which will then make additional requests for images and any other files that form a part of the page. Statistics measuring a website's popularity are usually based on the number of 'page views' or associated server 'hits', or file requests, which take place.

Having received the required files from the Web server, the browser then renders the page onto the screen as specified by its HTML, CSS, and other Web languages. Any images and other resources are incorporated to produce the on-screen Web page that the user sees.

Most Web pages will themselves contain hyperlinks to other related pages and perhaps to downloads, source documents, definitions and other Web resources. Such a collection of useful, related resources, interconnected via hypertext links, is what was dubbed a "web" of information. Making it available on the Internet created what Tim Berners-Lee first called the WorldWideWeb (a term written in CamelCase, subsequently discarded) in 1990.[1]

History

This NeXTcube used by Sir Tim Berners-Lee at CERN became the first Web server.

The underlying ideas of the Web can be traced as far back as 1980, when, at CERN in Switzerland, Sir Tim Berners-Lee built ENQUIRE (a reference to Enquire Within Upon Everything, a book he recalled from his youth). While it was rather different from the system in use today, it contained many of the same core ideas (and even some of the ideas of Berners-Lee's next project after the World Wide Web, the Semantic Web).

In March 1989, Berners-Lee wrote a proposal[2] which referenced ENQUIRE and described a more elaborate information management system. With help from Robert Cailliau, he published a more formal proposal for the World Wide Web on November 12, 1990.[3] The proposal was modeled after EBT's (Electronic Book Technology, a spin-off from the Institute for Research in Information and Scholarship at Brown University) Dynatext SGML reader that CERN had licensed. The Dynatext system, however technically advanced (a key player in the extension of SGML ISO 8879:1986 to Hypermedia within HyTime) was considered too expensive and with an inappropriate licensing policy for general HEP (High Energy Physics) community use: a fee for each document and each time a document was charged.

A NeXTcube was used by Berners-Lee as the world's first Web server and also to write the first Web browser, WorldWideWeb, in 1990. By Christmas 1990, Berners-Lee had built all the tools necessary for a working Web:[4] the first Web browser (which was a Web editor as well), the first Web server, and the first Web pages[5] which described the project itself.

On August 6, 1991, he posted a short summary of the World Wide Web project on the alt.hypertext newsgroup.[6] This date also marked the debut of the Web as a publicly available service on the Internet.

The first server outside of Europe was created at SLAC in December 1991 [7].

The crucial underlying concept of hypertext originated with older projects from the 1960s, such as the Hypertext Editing System (HES) at Brown University--- among others Ted Nelson and Andries van Dam--- Ted Nelson's Project Xanadu and Douglas Engelbart's oN-Line System (NLS). Both Nelson and Engelbart were in turn inspired by Vannevar Bush's microfilm-based "memex," which was described in the 1945 essay "As We May Think".

Berners-Lee's breakthrough was to marry hypertext to the Internet. In his book Weaving The Web, he explains that he had repeatedly suggested that a marriage between the two technologies was possible to members of both technical communities, but when no one took up his invitation, he finally tackled the project himself. In the process, he developed a system of globally unique identifiers for resources on the Web and elsewhere: the Uniform Resource Identifier.

The World Wide Web had a number of differences from other hypertext systems that were then available. The Web required only unidirectional links rather than bidirectional ones. This made it possible for someone to link to another resource without action by the owner of that resource. It also significantly reduced the difficulty of implementing Web servers and browsers (in comparison to earlier systems), but in turn presented the chronic problem of link rot. Unlike predecessors such as HyperCard, the World Wide Web was non-proprietary, making it possible to develop servers and clients independently and to add extensions without licensing restrictions.

On April 30, 1993, CERN announced[8] that the World Wide Web would be free to anyone, with no fees due. Coming two months after the announcement that the Gopher protocol was no longer free to use, this produced a rapid shift away from Gopher and towards the Web. An early popular Web browser was ViolaWWW, which was based upon HyperCard.

Scholars generally agree, however, that the turning point for the World Wide Web began with the introduction[9] of the Mosaic Web browser[10] in 1993, a graphical browser developed by a team at the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign (NCSA-UIUC), led by Marc Andreessen. Funding for Mosaic came from the High-Performance Computing and Communications Initiative, a funding program initiated by the High Performance Computing and Communication Act of 1991, one of several computing developments initiated by Senator Al Gore.[11] Prior to the release of Mosaic, graphics were not commonly mixed with text in Web pages, and its popularity was less than older protocols in use over the Internet, such as Gopher and Wide Area Information Servers (WAIS). Mosaic's graphical user interface allowed the Web to become, by far, the most popular Internet protocol.

The World Wide Web Consortium (W3C) was founded by Tim Berners-Lee after he left the European Organization for Nuclear Research (CERN) in October, 1994. It was founded at the Massachusetts Institute of Technology Laboratory for Computer Science (MIT/LCS) with support from the Defense Advanced Research Projects Agency (DARPA)—which had pioneered the Internet—and the European Commission.

Standards

Many formal standards and other technical specifications define the operation of different aspects of the World Wide Web, the Internet, and computer information exchange. Many of the documents are the work of the World Wide Web Consortium (W3C), headed by Berners-Lee, but some are produced by the Internet Engineering Task Force (IETF) and other organizations.

Usually, when Web standards are discussed, the following publications are seen as foundational:

  • Recommendations for markup languages, especially HTML and XHTML, from the W3C. These define the structure and interpretation of hypertext documents.
  • Recommendations for stylesheets, especially CSS, from the W3C.
  • Standards for ECMAScript (usually in the form of JavaScript), from Ecma International.
  • Recommendations for the Document Object Model, from W3C.

Additional publications provide definitions of other essential technologies for the World Wide Web, including, but not limited to, the following:

  • Uniform Resource Identifier (URI), which is a universal system for referencing resources on the Internet, such as hypertext documents and images. URIs, often called URLs, are defined by the IETF's RFC 3986 / STD 66: Uniform Resource Identifier (URI): Generic Syntax, as well as its predecessors and numerous URI scheme-defining RFCs;
  • HyperText Transfer Protocol (HTTP), especially as defined by RFC 2616: HTTP/1.1 and RFC 2617: HTTP Authentication, which specify how the browser and server authenticate each other.

Privacy

"We are left with the alarming question as to whether privacy should be put before global security." wrote Abhilash Sonwane of Cyberoam.[12] Among services paid for by advertising, Yahoo! could collect the most data about commercial Web users, about 2,500 bits of information per month about each typical user of its site and its affiliated advertising network sites. Yahoo! was followed by MySpace with about half that potential and then by AOL-TimeWarner, Google, Facebook, Microsoft, and eBay.[13] About 27% of websites operated outside .com addresses.[14]

Security

The Web has become criminals' preferred pathway for spreading malware. Cybercrime carried out on the Web can include identity theft, fraud, espionage and intelligence gathering.[15] Web-based vulnerabilities now outnumber traditional computer security concerns,[16] and as measured by Google, about one in ten Web pages may contain malicious code.[17] Most Web-based attacks take place on legitimate websites, and most, as measured by Sophos, are hosted in the United States, China and Russia.[18]

The most common of all malware threats is SQL injection attacks against websites.[19] Through HTML and URIs the Web was vulnerable to attacks like cross-site scripting (XSS) that came with the introduction of JavaScript[20] and were exacerbated to some degree by Web 2.0 and Ajax web design that favors the use of scripts.[21] Today by one estimate, 70% of all websites are open to XSS attacks on their users.[22]

Proposed solutions vary to extremes. Large security vendors like McAfee already design governance and compliance suites to meet post-9/11 regulations,[23] and some, like Finjan have recommended active real-time inspection of code and all content regardless of its source.[15] Some have argued that for enterprise to see security as a business opportunity rather than a cost center,[24] "ubiquitous, always-on digital rights management" enforced in the infrastructure by a handful of organizations must replace the hundreds of companies that today secure data and networks.[25] Jonathan Zittrain has said users sharing responsibility for computing safety is far preferable to locking down the Internet.[26]

Web Accessibility

Many countries regulate web accessibility as a requirement for web sites.

Java

A significant advance in Web technology was Sun Microsystems' Java platform. It enables Web pages to embed small programs (called applets) directly into the view. These applets run on the end-user's computer, providing a richer user interface than simple Web pages. Java client-side applets never gained the popularity that Sun had hoped for a variety of reasons, including lack of integration with other content (applets were confined to small boxes within the rendered page) and the fact that many computers at the time were supplied to end users without a suitably installed Java Virtual Machine, and so required a download by the user before applets would appear. Adobe Flash now performs many of the functions that were originally envisioned for Java applets, including the playing of video content, animation, and some rich GUI features. Java itself has become more widely used as a platform and language for server-side and other programming.

JavaScript

JavaScript, on the other hand, is a scripting language that was initially developed for use within Web pages. The standardized version is ECMAScript. While its name is similar to Java, JavaScript was developed by Netscape and has very little to do with Java, although the syntax of both languages is derived from the C programming language. In conjunction with a Web page's Document Object Model (DOM), JavaScript has become a much more powerful technology than its creators originally envisioned.[citation needed] The manipulation of a page's DOM after the page is delivered to the client has been called Dynamic HTML (DHTML), to emphasize a shift away from static HTML displays.

In simple cases, all the optional information and actions available on a JavaScript-enhanced Web page will have been downloaded when the page was first delivered. Ajax ("Asynchronous JavaScript and XML") is a group of interrelated web development techniques used for creating interactive web applications that provide a method whereby parts within a Web page may be updated, using new information obtained over the network at a later time in response to user actions. This allows the page to be more responsive, interactive and interesting, without the user having to wait for whole-page reloads. Ajax is seen as an important aspect of what is being called Web 2.0. Examples of Ajax techniques currently in use can be seen in Gmail, Google Maps, and other dynamic Web applications.

Publishing Web pages

Web page production is available to individuals outside the mass media. In order to publish a Web page, one does not have to go through a publisher or other media institution, and potential readers could be found in all corners of the globe.

Many different kinds of information are available on the Web, and for those who wish to know other societies, cultures, and peoples, it has become easier.

The increased opportunity to publish materials is observable in the countless personal and social networking pages, as well as sites by families, small shops, etc., facilitated by the emergence of free Web hosting services.

Statistics

According to a 2001 study, there were massively more than 550 billion documents on the Web, mostly in the invisible Web, or deep Web.[27] A 2002 survey of 2,024 million Web pages[28] determined that by far the most Web content was in English: 56.4%; next were pages in German (7.7%), French (5.6%), and Japanese (4.9%). A more recent study, which used Web searches in 75 different languages to sample the Web, determined that there were over 11.5 billion Web pages in the publicly indexable Web as of the end of January 2005.[29] As of June 2008, the indexable web contains at least 63 billion pages.[30] On July 25, 2008, Google software engineers Jesse Alpert and Nissan Hajaj announced that Google Search had discovered one trillion unique URLs.[31]

Over 100.1 million websites operated as of March 2008.[14] Of these 74% were commercial or other sites operating in the .com generic top-level domain.[14]

Speed issues

Frustration over congestion issues in the Internet infrastructure and the high latency that results in slow browsing has led to an alternative, pejorative name for the World Wide Web: the World Wide Wait.[citation needed] Speeding up the Internet is an ongoing discussion over the use of peering and QoS technologies. Other solutions to reduce the World Wide Wait can be found on W3C.

Standard guidelines for ideal Web response times are:[32]

  • 0.1 second (one tenth of a second). Ideal response time. The user doesn't sense any interruption.
  • 1 second. Highest acceptable response time. Download times above 1 second interrupt the user experience.
  • 10 seconds. Unacceptable response time. The user experience is interrupted and the user is likely to leave the site or system.

These numbers are useful for planning server capacity.

Caching

If a user revisits a Web page after only a short interval, the page data may not need to be re-obtained from the source Web server. Almost all Web browsers cache recently-obtained data, usually on the local hard drive. HTTP requests sent by a browser will usually only ask for data that has changed since the last download. If the locally-cached data is still current, it will be reused.

Caching helps reduce the amount of Web traffic on the Internet. The decision about expiration is made independently for each downloaded file, whether image, stylesheet, JavaScript, HTML, or whatever other content the site may provide. Thus even on sites with highly dynamic content, many of the basic resources only need to be refreshed occasionally. Web site designers find it worthwhile to collate resources such as CSS data and JavaScript into a few site-wide files so that they can be cached efficiently. This helps reduce page download times and lowers demands on the Web server.

There are other components of the Internet that can cache Web content. Corporate and academic firewalls often cache Web resources requested by one user for the benefit of all. (See also Caching proxy server.) Some search engines, such as Google or Yahoo!, also store cached content from websites.

Apart from the facilities built into Web servers that can determine when files have been updated and so need to be re-sent, designers of dynamically-generated Web pages can control the HTTP headers sent back to requesting users, so that transient or sensitive pages are not cached. Internet banking and news sites frequently use this facility.

Data requested with an HTTP 'GET' is likely to be cached if other conditions are met; data obtained in response to a 'POST' is assumed to depend on the data that was POSTed and so is not cached.

Link rot and Web archival

Over time, many Web resources pointed to by hyperlinks disappear, relocate, or are replaced with different content. This phenomenon is referred to in some circles as "link rot" and the hyperlinks affected by it are often called "dead links".

The ephemeral nature of the Web has prompted many efforts to archive Web sites. The Internet Archive is one of the most well-known efforts; it has been active since 1996.

Academic conferences

The major academic event covering the Web is the World Wide Web Conference, promoted by IW3C2.

WWW prefix in Web addresses

The letters "www" are commonly found at the beginning of Web addresses because of the long-standing practice of naming Internet hosts (servers) according to the services they provide. So for example, the host name for a Web server is often "www"; for an FTP server, "ftp"; and for a USENET news server, "news" or "nntp" (after the news protocol NNTP). These host names appear as DNS subdomain names, as in "www.example.com".

This use of such prefixes is not required by any technical standard; indeed, the first Web server was at "nxoc01.cern.ch",[33] and even today many Web sites exist without a "www" prefix. The "www" prefix has no meaning in the way the main Web site is shown. The "www" prefix is simply one choice for a Web site's host name.

However, some website addresses require the www. prefix, and if typed without one, won't work; there are also some which must be typed without the prefix.

Some Web browsers will automatically try adding "www." to the beginning, and possibly ".com" to the end, of typed URLs if no host is found without them. All major web browser will also prefix "http://www." and append ".com" to the address bar contents if the Control and Enter keys are pressed simultaneously. For example, entering "example" in the address bar and then pressing either just Enter or Control+Enter will usually resolve to "http://www.example.com", depending on the exact browser version and its settings.

Pronunciation of "www"

In English, "www" is pronounced "double-you double-you double-you". It is sometimes shortened to "triple-double-you" or "dub, dub, dub".

The English writer Douglas Adams once quipped:

The World Wide Web is the only thing I know of whose shortened form takes three times longer to say than what it's short for.

Douglas Adams, The Independent on Sunday, 1999

It is also interesting that in Mandarin Chinese, "World Wide Web" is commonly translated via a phono-semantic matching to wàn wéi wǎng (万维网), which satisfies "www" and literally means "myriad dimensional net",[34] a translation that very appropriately reflects the design concept and proliferation of the World Wide Web.

See also

Notes

  1. ↑ "WorldWideWeb: Proposal for a HyperText Project", Tim Berners-Lee & Robert Cailliau, 1990
  2. ↑ Information Management: A Proposal
  3. ↑ Proposal for the World Wide Web
  4. ↑ Tim Berners-Lee: WorldWideWeb, the first Web client
  5. ↑ First Web pages
  6. ↑ Short summary of the World Wide Web project
  7. ↑ The Early World Wide Web at SLAC: Early Chronology and Documents
  8. ↑ Ten Years Public Domain for the Original Web Software
  9. ↑ Mosaic Web Browser History - NCSA, Marc Andreessen, Eric Bina
  10. ↑ NCSA Mosaic - September 10, 1993 Demo
  11. ↑ Vice President Al Gore's ENIAC Anniversary Speech
  12. ↑ Sonwane, Abhilash. "The cost of online anonymity", (preview via virusbtn.com) Virus Bulletin, October 2008. Retrieved 2008-09-26.
  13. ↑ Story, Louise and comScore. "They Know More Than You Think", March 10, 2008. in Story, Louise. "To Aim Ads, Web Is Keeping Closer Eye on You", The New York Times, The New York Times Company, March 10, 2008. Retrieved 2008-03-09.
  14. ↑ 14.0 14.1 14.2 Domain Counts & Internet Statistics. Name Intelligence. Retrieved 2008-03-11.
  15. ↑ 15.0 15.1 Ben-Itzhak, Yuval. "Infosecurity 2008 - New defence strategy in battle against e-crime", ComputerWeekly, Reed Business Information, April 18, 2008. Retrieved 2008-04-20.
  16. ↑ XSS vulnerabilties outnumbered buffer overflows, in Christey, Steve and Martin, Robert A. (May 22, 2007). Vulnerability Type Distributions in CVE (version 1.1). MITRE Corporation. Retrieved 2008-06-07. During the second half of 2007, XSS outnumbered "traditional" vulnerabilities, in Symantec Internet Security Threat Report: Trends for July-December 2007 (Executive Summary) (PDF) pp. 1–2. Symantec Corp. (April 2008). Retrieved 2008-05-11.
  17. ↑ "Google searches web's dark side", BBC News, May 11, 2007. Retrieved 2008-04-26.
  18. ↑ Security Threat Report (PDF). Sophos (Q1 2008). Retrieved 2008-04-24.
  19. ↑ Security threat report (PDF). Sophos (July 2008). Retrieved 2008-08-24.
  20. ↑ Fogie, Seth, Jeremiah Grossman, Robert Hansen, and Anton Rager (2007). Cross Site Scripting Attacks: XSS Exploits and Defense (PDF), Syngress, Elsevier Science & Technology, 68–69, 127. ISBN 1597491543. Retrieved 2008-06-06. 
  21. ↑ O'Reilly, Tim (September 30, 2005). What Is Web 2.0 pp. 4–5. O'Reilly Media. Retrieved 2008-06-04. and AJAX web applications can introduce security vulnerabilities like "client-side security controls, increased attack surfaces, and new possibilities for Cross-Site Scripting (XSS)", in Ritchie, Paul (March 2007). The security risks of AJAX/web 2.0 applications. Infosecurity. which cites Hayre, Jaswinder S. and Kelath, Jayasankar. "Ajax Security Basics", SecurityFocus, June 22, 2006. Retrieved 2008-06-06.
  22. ↑ Berinato, Scott. "Software Vulnerability Disclosure: The Chilling Effect", CSO, CXO Media, January 1, 2007, p. 7. Retrieved 2008-06-07.
  23. ↑ Prince, Brian. "McAfee Governance, Risk and Compliance Business Unit", eWEEK, Ziff Davis Enterprise Holdings, April 9, 2008. Retrieved 2008-04-25.
  24. ↑ Preston, Rob. "Down To Business: It's Past Time To Elevate The Infosec Conversation", InformationWeek, United Business Media, April 12, 2008. Retrieved 2008-04-25.
  25. ↑ Claburn, Thomas. "RSA's Coviello Predicts Security Consolidation", InformationWeek, United Business Media, February 6, 2007. Retrieved 2008-04-25.
  26. ↑ Duffy Marsan, Carolyn, "How the iPhone is killing the 'Net", Network World, IDG, April 9, 2008. Retrieved 2008-04-17.
  27. ↑ The 'Deep' Web: Surfacing Hidden Value
  28. ↑ Distribution of languages on the Internet
  29. ↑ Indexable Web Size
  30. ↑ The size of the World Wide Web
  31. ↑ Alpert, Jesse; Hajaj, Nissan (2008-07-25). We knew the web was big.... The Official Google Blog.
  32. ↑ Nielsen 1999, `Designing Web Usability', page 42
  33. ↑ Frequently asked questions by the Press - Tim Berners-Lee
  34. ↑ See CEDICT or the MDBG Chinese-English Dictionary.

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ar:شبكة عنكبوتية عالمية ast:World Wide Web ba:Бөтә Донъя Селтәре bs:World Wide Web br:World Wide Web bg:World Wide Web ca:World Wide Web cs:World Wide Web cy:Gwe fyd-eang da:World Wide Web de:World Wide Web et:Veeb el:Παγκόσμιος Ιστός eml:Gran Tlarè mundièl es:World Wide Web eo:TTT eu:World Wide Web fa:وب جهان‌گستر fo:World Wide Web fr:World Wide Web ga:Gréasán Domhanda gl:World Wide Web ko:월드 와이드 웹 hi:विश्व व्यापी वेब hr:World Wide Web ilo:Web id:World Wide Web ia:World Wide Web is:Veraldarvefurinn it:World Wide Web he:World Wide Web kk:Ғаламтор ku:World Wide Web lad:Web la:Tela totius terrae lv:Globālais tīmeklis lb:World Wide Web lt:Žiniatinklis hu:Világháló mk:World Wide Web ml:വേള്‍ഡ് വൈഡ് വെബ് ms:Jaringan Sejagat my:၀က်ဘ် nl:Wereldwijd web ja:World Wide Web no:World Wide Web nn:Verdsveven ps:WWW pl:World Wide Web pt:World Wide Web ro:World Wide Web rm:World Wide Web ru:Всемирная паутина sah:World Wide Web sq:World Wide Web scn:World Wide Web si:විශ්ව ව්‍යාප්ත වියමන simple:World Wide Web sk:World Wide Web sl:Splet so:World Wide Web sr:WWW sh:World Wide Web fi:World Wide Web sv:World Wide Web kab:World Wide Web th:เวิลด์ไวด์เว็บ vi:World Wide Web tr:Dünya Çapında Ağ uk:Всесвітня павутина ur:حبالہ محیط عالم vec:Web zh-yue:萬維網 zh:万维网

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