Telnet allows you to log into other computers on the Internet and use them just as if you were at that computer's keyboard. It also alows you to connect to online bulletin boards and discussions. Many universities hold online discussions that require you to telnet to their system.
To telnet to a system simply click on START, then click on RUN. Now type:
Telnet <system name>
This command connects you to the system "nyx.net." From there you get a login prompt to this system. What happens next is up to the system you are connected to.