Internet is a computer network that connects millions of computers across a number of countries. There is no central authority that controls the Internet; different organizations own different pieces of it. The Internet was originally conceived of by the Advanced Research Project Agency (ARPA) of the U.S. government in the 1960s.

The World Wide Web (or "the Web" for short) refers to that portion of the computers on the Internet that can communicate with each other using a computer-network protocol called HTTP. All browsers use HTTP to request and receive Web pages from other computers.

We have used the words page and place interchangeably when referring to the Web. Another synonymous term is site, as in Web site. All three terms refer to locations on the Web that you can visit and view through a browser.

An Internet Service Provider (ISP) is any one of a number of companies that enable people like you and me not only to connect to the Internet and surf the Web but also to publish Web pages.

There is no one to certify that the information presented on the Web is accurate<精確的>, correct, and up-to-date.

A search engine is a program that allows one to search for keywords in files at one or more Internet sites. Popular search engines include Lycos, Excite, and AltaVista.