Although the Internet is one large network utilising millions of computers, it is in fact made up of many networks. There are estimated to be about 15,000 networks which are owned by individuals, companies, educational institutions, government agencies and Internet Service Providers. It is difficult to calculate exactly how big the Internet is or how many people use it. The Internet is made up of over 15,000 smaller networks spanning over 140 countries. When calculating the number of people on the Internet there are two calculations to consider.
Many large corporations connect their corporate email systems to the Internet.
Employees can send and receive Internet mail via their corporate email system but they can t access all the other function such as the World Wide Web, FTP etc. Informative pages consisting of text, graphics, sounds, video clips and more can be placed on the Internet. Like a magazine a Web Site can be used as a mass communication medium. The most significant difference however, is that a web site can be interactive and dynamic. With an interactive and dynamic web site, the information the user accesses is continually updated.