On the Internet there are a number of protocols built on the basic protocols of TCP / IP, and offering diverse services. Speaking about the application protocols, services, Internet services offered by the network and the opportunities provided by Internet, we're talking about the same. There are only a few basic services on the Internet. The most common service in the early days of the Internet was Telnet. It allows you to turn your PC into a remote terminal another computer. Terminal of a conventional computer is different because it does not perform its own calculations. Everything you type on your keyboard to a remote computer. The remote computer runs the program, perform the necessary calculations and searches for information.
The results are passed back and displayed on your monitor. You like working on a remote computer, staying in the workplace. As remote computers are mostly used machines running the operating system UNIX, so to work in terminal mode commands require knowledge of the system. With the development of graphical operating systems such as Windows, the command mode of operation has become less popular, and the Telnet service in recent times is almost never used. Many information systems that were previously available only via Telnet, now available from the World web, which will be discussed below. E-mail or e-mail has long been the most common and cheapest means of information exchange. As a means of communication, it does not differ from the usual mail, but it works much faster.