World Wide Web: Encyclopedia - World Wide Web

World Wide Web

The World Wide Web ("WWW" or simply the "Web") is an information space in which the items of interest, referred to as resources, are identified by global identifiers called Uniform Resource Identifiers (URIs). The term is often mistakenly used as a synonym for the Internet, but the Web is actually a service that operates over the Internet. (Find more information at this link.)

World Wide Web - Basic terms

The World Wide Web is the combination of four basic ideas:

• hypertext, that is the ability, in a computer environment, to move from one part of a document to another or from one document to another through internal connections among these documents (called "hyperlinks");

• computer network addresses, that is the ability, on a computer network, to locate a particular computer on the network through a unique address;

• the client-server model of computing, in which client software or a client computer makes requests of server software or a server computer that provides the client with resources or services, such as data or files; and

• markup language, in which characters or codes embedded in text indicate to a computer how to print or display the text, e.g. as in italics or bold type or font.

On the World Wide Web, a client program called a web browser retrieves information resources, such as web pages and other computer files, from web servers using their network addresses and displays them, typically on a computer monitor, using a markup language that determines the details of the display. One can then follow hyperlinks in each page to other resources on the World Wide Web of information whose location is provided by these hyperlinks. It is also possible, for example by filling in and submitting web forms, to send information back to the server to interact with it. The act of following hyperlinks is often called "browsing" or "surfing" the Web. Web pages are often arranged in collections of related material called "websites."

The phrase "surfing the Internet" was first popularised in print by Jean Armour Polly, a librarian, in an article called Surfing the INTERNET, published in the Wilson Library Bulletin in June, 1992. Although Polly may have developed the phrase independently, slightly earlier uses of similar terms have been found on the Usenet from 1991 and 1992, and some recollections claim it was also used verbally in the hacker community for a couple years before that. Polly is famous as "NetMom" in the history of the Internet.

For more information on the distinction between the World Wide Web and the Internet itself — as in everyday use the two are sometimes confused — see Dark internet where this is discussed in more detail.

Although the English word worldwide is normally written as one word (without a space or hyphen), the proper name World Wide Web and abbreviation WWW are now well-established even in formal English. The earliest references to the Web called it the WorldWideWeb (an example of computer programmers' fondness for intercaps) or the World-Wide Web (with a hyphen, this version of the name is the closest to normal English usage).

Ironically, the abbreviation "WWW" is impractical as it contains more syllables than the full term "World Wide Web", and thus takes longer to say. It is, however, easier to type.

World Wide Web - How the Web works

When you want to access a web page, or other "resource", on the World Wide Web, you normally begin either by typing the URL of the page into your 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 next step is for an HTTP request to be sent to the web server working at that IP address for the page required. In the case of a typical web page, the HTML text, graphics and any other files that form a part of the page will be requested and returned to the client in quick succession.

The web browser's job is then to render the page as described by the HTML, CSS and other files received, incorporating the images, links and other resources as necessary. This produces the on-screen 'page' that you see.

Most web pages will, themselves, contain hyperlinks to other relevant and informative 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 has been dubbed a 'web' of information. Making it available on the Internet produced what Tim Berners-Lee first called the World Wide Web in the early 1990s [1] [2].

World Wide Web - Origins

See also: History of the Internet

The underlying ideas of the Web can be traced as far back as 1980, when Tim Berners-Lee and Robert Cailliau built ENQUIRE (referring to Enquire Within Upon Everything, a book Berners-Lee recalled from his youth). While it was rather different from the Web we 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).

In March 1989, Tim Berners-Lee wrote "Information Management: A Proposal", which referenced ENQUIRE and described a more elaborate information management system. [3] He published a more formal proposal for the actual World Wide Web on November 12, 1990 [4]. Implementation began on November 13, 1990 when Berners-Lee wrote the first Web page on a NeXT workstation.

During the Christmas holiday of that year, Berners-Lee built all the tools necessary for a working Web [5]: the first Web browser (which was a Web editor as well) and the first Web server.

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

The crucial underlying concept of hypertext originated with older projects from the 1960s, such as 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 brilliant 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 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 broken links.

• Unlike certain applications, 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 that the World Wide Web would be free to anyone, with no fees due.

The World Wide Web finally gained critical mass with the 1993 release of the graphical Mosaic web browser by the National Center for Supercomputing Applications developed by Marc Andreessen. Prior to the release of Mosaic, the Web was text based and its popularity was less than older protocols in use over the Internet, such as Gopher and WAIS. Mosaics graphical user interface allowed the Web to become by far the most popular Internet protocol.

World Wide Web - Web standards

At its core, the Web is made up of three standards:

• the Uniform Resource Identifier (URI), which is a universal system for referencing resources on the Web, such as Web pages;
• the HyperText Transfer Protocol (HTTP), which specifies how the browser and server communicate with each other; and
• the HyperText Markup Language (HTML), used to define the structure and content of hypertext documents.

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.

World Wide Web - Java and JavaScript

Another significant advance in the technology was Sun Microsystems' Java programming language. It initially enabled Web servers to embed small programs (called applets) directly into the information being served, and these applets would run on the end-user's computer, allowing faster and richer user interaction. Eventually, it came to be more widely used as a tool for generating complex server-side content as it is requested. Java never gained as much acceptance as Sun had hoped as a platform for client-side applets for a variety of reasons, including lack of integration with other content (applets were confined to small boxes within the rendered page) and poor perfomance (particularly start up delays) of Java VMs on PC hardware of that time.

JavaScript, however, is a scripting language that was developed for Web pages. The standardised version is ECMAScript. While its name is similar to Java, it was developed by Netscape and not Sun Microsystems, and it has almost nothing to do with Java, with the only exception being that like Java its syntax is derived from the C programming language. Like Java, Javascript is also object oriented but like C++ and unlike Java, it allows mixed code - both object oriented as well as procedural. In conjunction with the Document Object Model, JavaScript has become a much more powerful language than its creators originally envisioned. Sometimes its usage is expressed under the term Dynamic HTML (DHTML), to emphasise a shift away from static HTML pages.

World Wide Web - Sociological implications

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. And 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.

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.

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.

World Wide Web - 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.

Unlike books and documents, hypertext does not have a linear order from beginning to end. It is not broken down into the hierarchy of chapters, sections, subsections, etc.

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 travelling 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.

Although some websites are available in multiple languages, many are in the local language only. Also, not all software supports all special characters, and RTL languages. These factors would challenge the notion that the World Wide Web will bring a unity to the world.

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.

World Wide Web - Statistics

According to a 2001 study [6], there were more than 550 billion documents on the Web, mostly in the "invisible Web". A 2002 survey of 2,024 million web pages [7] 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 [8] which used web searches in 75 different languages to sample the Web determined that there were over 11.5 billion web pages in the publically-indexable Web as of January 2005.

World Wide Web - Speed issues

Frustration over congestion issues in the Internet infrastructure and the high latency that results in slow browsing has lead 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 QoS technologies. Other solutions to reduce the World Wide Wait can be found on W3C.

World Wide Web - Academic conferences

The major academic event covering the WWW is the World Wide Web series of conferences, promoted by IW3C2. There is a list with links to all conferences in the series.

World Wide Web - Pronunciation of www

Most English-speaking people pronounce the 9-syllable letter sequence www used in some domain names for websites as "double U, double U, double U" despite shorter options like "triple double U", triple dub or even "World Wide Web" being available.

Some languages do not have the letter w in their alphabet (for example, Italian), which leads some people to pronounce www as "vou, vou, vou." In some languages (such as Czech and Finnish) the w is substituted by a v, so Czechs pronounce www as "veh, veh, veh" rather than the correct but much longer pronunciation "dvojité veh, dvojité veh, dvojité veh;" the same applies to Finnish, where the correct pronunciation would be "kaksoisvee, kaksoisvee, kaksoisvee." Also in Norwegian, and similarly in Swedish and Danish: Instead of the correct "dobbel-ve, dobbel-ve, dobbel-ve" it is pronounced "ve, ve, ve". The pronunciation of "ve" instead of "dobbel-ve" is also used in other abbreviations. Several other languages (e.g. German, Dutch etc.) simply pronounce the letter W as a single syllable, so this problem doesn't occur. In French "trois fois double-vé" is probably the most common pronounciation.

Depending on how the domain and web server are set up, a www website can often be accessed without entering the "www.", as long as the ".com" or other appropriate top-level domain is appended. Even this is not always necessary as some browsers will automatically try adding "www." and ".com" to typed URIs if a web page isn't found without them.

In English pronunciation, saying the full words "World Wide Web" takes one-third as many syllables as saying the initialism "www". According to Berners-Lee, others mentioned this fact as a reason to choose a different name, but he persisted.

Another, less common way of saying "www" is w3, or double u to the power of 3, power because the 3 in w3 is superscripted. However, the use of this initialism is uncommon. One further way is used by those wishing to speed up the full pronounciations by saying "All the double-U s"

In New Zealand and occasionally in Australia, "www" is often pronounced "dub-dub-dub". This is widely accepted (for example its use in TV commercials appears standard) and is more concise than some other renditions in English.

In the Southern United States the two syllable pronunciation of the letter w "dub-ya" is often used, resulting in dub-ya-dub-ya-dub-ya, even when spoken by persons who would normally use the "standard English" three syllable pronunciation for a single letter w.

See also

• History of the Internet
• Semantic Web
• Media studies
• Smartphone
• List of websites
• Search engine
• Web directory
• Hypertext
• First image on the Web
• Streaming media
• Cyberzine
• Interweb
• Web 2.0, term often applied to perceived ongoing transition of the WWW from a collection of websites to a full-fledged computing platform serving web applications

Adapted from the Wikipedia article "World Wide Web", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki