These computers are typically maintained by large education or research institutions. There are also millions of relatively smaller computers which are connected to the Internet. Depending on the type of system the client may have a direct connection onto the Internet or has an account which requires that they log in via a modem and telephone line. ISPs range from small local companies to large international companies like America On-Line, CompuServe and Prodigy. Internet communications can take several forms.
Some individuals only have access a small number of Internet resources.
Next we will briefly describe the major forms of communication on the Internet. E-mail is fairly easy to use. The domain name tells the Internet computers where to route the message just like a street address on a regular piece of mail. Don't worry about upper case and lower case letters, mail servers are typically not case sensitive. Discussion groups on the Internet come in several forms.