The Internet enables many different kinds of communication, each of which needs a software application to make it work on your computer, like a Web browser or an email client. In fact, one of the mistakes many people make is thinking that the World Wide Web and the Internet are the same thing. The Internet is the backbone that connects computers and networks of computers to one another. The Web is one way to access specific content. It's much younger than the Internet and, in fact, the Web's ability to show graphics and animation is one of the key reasons why the Internet became so popular in the mid 1990s.
Email is another main component and tool of the Internet.
The power of the Internet is that any person can communicate to one person or millions of people at the same time, and they can all communicate back in the same way or to each other. Think of the Internet as illustrated in this picture and as explained below. Computers and other hardware devices are connected by telephone lines and other telecommunication pipelines, such as cables, satellites, and fiber optic lines allowing any computer to pass messages, commands and files to any other computer that has the software to understand them. The computer that holds the file you are trying to get is called a server, and you are referred to as a client or user. Because the Internet is all about interconnected communication, the same computer can be both a client and a server at different times.