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).