The World Wide Web ("WWW", or simply "Web") is an information space in which the items of interest, referred to as resources, are identified by global identifiers called Uniform Resource Identifiers (URI). The term is often mistakenly used as a synonym for the Internet, but the Web is actually a service that operates over the Internet.
Hypertext is viewed using a program called a web browser which retrieves pieces of information, called "documents" or "web pages", from web servers and displays them, typically on a computer monitor. One can then follow hyperlinks on each page to other documents or even send information back to the server to interact with it. The act of following hyperlinks is often called "surfing" or "browsing" the web. Web pages are often arranged in collections of related material called "web sites."
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).
See also: History of the Internet
The Web can be traced back to a project at CERN in 1989 when Tim Berners-Lee and Robert Cailliau built ENQUIRE (short for 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, the Semantic Web). Berners-Lee mentions that much of the motivation behind the project was so that he could access library information that was scattered on several different servers at CERN.
Tim Berners-Lee published a more formal proposal for the actual World Wide Web on November 12, 1990  and wrote the first web page  on November 13 on a NeXT workstation. Over Christmas of that year Berners-Lee built all the tools necessary for a working Web , the first actual 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 WorldWideWeb project on the alt.hypertext newsgroup.
The primary underlying concept of hypertext came from earlier efforts, 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 in place.
- 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 or Gopher, 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 three standards
The Web is made up of three standards: The Uniform Resource Locator (URL), which specifies how each page of information is given a unique "address" at which it can be found; Hyper Text Transfer Protocol (HTTP), which specifies how the browser and server send the information to each other, and Hyper Text Markup Language (HTML), a method of encoding the information so it can be displayed on a variety of devices. Berners-Lee now heads the World Wide Web Consortium (W3C), which develops and maintains these standards and others that enable computers on the Web to effectively store and communicate all kinds of information.
The initial "www" program at CERN displayed styled text and images, and it was a WYSIWYG HTML editor as well as the browser.
As it ran only on NeXT machines, CERN released a simple, text-only version to the world. Some journalists first encountered the Web through the text browser written by Nicola Pellow and this engendered a myth that the Web was text-only until Mosaic came along. The Web had graphics from the start, at least for NeXT users. However, Mosaic did introduce the ability to combine text and images in a single page.
Meanwhile, browsers such as Tony Johnson's "Midas" and Pei-Yuan Wei's Viola (1991) added the ability to display graphics also on other Unix machines. Marc Andreessen of NCSA released a browser called "Mosaic for X" in 1993 that sparked a tremendous rise in the popularity of the Web among novice users. Andreesen went on to found Mosaic Communications Corporation (now Netscape Communications, a unit of Time Warner). Additional features such as dynamic content, music and animation can be found in modern browsers.
Browser makers do not always adhere to the standards set forth by the W3C, so it is not uncommon for these newer features not to work properly on all computers, and the web as seen by Netscape or Mozilla Firefox is not quite the same as the web seen by Internet Explorer. The ever-improving technical capability of the WWW has enabled the development of real-time web-based services such as webcasts, web radio and live web cams.
Another significant advance in the technology was Sun Microsystems' Java programming language, which enabled web servers to embed small programs (called applets) directly into the information being served that would run on the user's computer, allowing faster and richer user interaction.
The exponential growth of the Internet was primarily attributed to the emergence of the web browser Mosaic, followed by its commercial offspring Netscape Navigator, during the mid-1990s.
It brought unprecedented attention to the Internet from media, industries, policy makers, and the general public.
Eventually, it led to several visions of how our society might change, although some point out that those visions are not unique to the Internet, but repeated with many new technologies (especially information and communications technologies) of various era.
Because the web is global in scale, some suggested that it will nurture mutual understanding on a global scale.
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.
According to a 2002 survey of 2,024 million web pages , 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%).
According to a 2001 study , there were more than 550 billion documents on the web, mostly in the "invisible web".
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 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.
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.
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", but many shorter pronunciations can be heard: "triple double U", "double U, double U" (omitting one W), "dub, dub, dub", "hex u", etc. Some languages do not have the letter w in their alphabet (for example, Italian), which leads to some people pronouncing www as "vou, vou, vou." Perhaps a shorter pronunciation will become standard usage in the future.
Depending on how the domain and web server is set up, a www website can often be accessed without mentioning 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.
It is interesting to point out that, in English at least, saying the full words "World Wide Web" takes three times fewer syllables than saying the acronym "WWW".