The World Wide Web is the most popular part of the Internet by far.  You can think of the WWW as a network of electronic files stored on computers all around the world. The collection of all Web sites on the Internet is referred to as the World Wide Web.

Hypertext links these resources together. Uniform Resource Locators or URLs are the addresses used to locate these files. The information contained in a URL gives you the ability to jump from one web page to another with just a click of your mouse. When you type a URL into your browser or click on a hypertext link, your browser sends a request to a remote computer, called a web server, to download one or more files.

The Web physically consists of your personal computer, web browser software, a connection to an Internet service provider, computers called servers that host digital data, and routers and switches to direct the flow of information.

The "glue" that holds the Web together is called hypertext and hyperlinks. This feature allows electronic files on the Web to be linked so you can jump easily between them. On the Web, you navigate through pages of information--commonly known as browsing or surfing--based on what interests you at that particular moment.

To access the Web you need a web browser, such as Netscape Navigator or Microsoft Internet Explorer. How does your web browser distinguish between web pages and other types of data on the Internet? Web pages are written in a computer language called Hypertext Markup Language or HTML.

Other Components of the Internet

E-Mail
Electronic mail, or e-mail, allows computer users locally and worldwide to exchange messages. Each user of e-mail has a mailbox address to which messages are sent. Messages sent through e-mail can arrive within a matter of seconds.

E-mail Discussion Groups
The Internet is home to a large community of individuals who carry out active discussions organized around topic-oriented forums distributed by e-mail. These are administered by software programs. Probably the most common program is the listserv.   When you subscribe to a listserv, messages from other subscribers are automatically sent to your electronic mailbox.

Telnet
Telnet is a program that allows you to log into computers on the Internet and use online databases, library catalogs, chat services, and more

FTP
FTP or File Transfer Protocol is both a program and the method used to transfer files between computers. Anonymous FTP is an option that allows users to transfer files from thousands of host computers on the Internet to their personal computer account. FTP sites contain books, articles, software, games, images, sounds, multimedia, course work, data sets, and more

Usenet News
Usenet News is a global electronic bulletin board system in which millions of computer users exchange information on a vast range of topics. The major difference between Usenet News and e-mail discussion groups is the fact that Usenet messages are stored on central computers, and users must connect to these computers to read or download the messages posted to these groups. This is distinct from e-mail distribution, in which messages arrive in the electronic mailboxes of each list member.

Chat & Instant Messenging
Chat programs allow users on the Internet to communicate with each other by typing in real time. They are sometimes included as a feature of a Web site, where users can log into the "chat room" to exchange comments and information about the topics addressed on the site.
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A variation of chat is the phenomenon of instant messenging. With instant messenging, a user on the Web can contact another user currently logged in and type a conversation. America Online's IM, ICQ, MSN and Yahoo are some commonly-used chat programs.