What's the difference between the Internet and the Web? A lot. The Internet is a global collection of "Interconnected networks". It is also the basis upon which other technologies--the Web, email and grid computing--are built.

IS EVERY COMPUTER PART OF A NETWORK?

Every computer connected to the Internet is part of a network. Every time you connect to the Internet, you actually connect to a smaller network provided by an Internet Service Provider (ISP). The ISP then connects to a larger network and you become part of that network also. (At work, you may be part of a local area network (LAN), which may still connect to the Internet using an ISP.)

Computers connected to the Internet can communicate with each other, but "being connected" is not just a question of connecting cables: computers must also "speak the same language". For the Internet, this common language is called the Transmission Control Protocol/Internet Protocol or TCP/IP.

WHAT IS A "PROTOCOL"?

A protocol is a way to send data between two devices. The TCP/IP protocol determines, for instance,

• the type of error checking to be used
• the data compression method (if any)
• how the sending device will indicate that it has finished sending
• how the receiving device will indicate that it has finished receiving.

WHAT ABOUT EMAIL AND THE WORLD WIDE WEB?

The World Wide Web is an information-sharing service built on top of the Internet. It uses HTTP, which stands for "HyperText Transfer Protocol".

E-mail uses the Simple Mail Transfer Protocol (SMTP), and file transferuses the "File Transfer Protocol" (FTP). These services are also built on top of the Internet.