Telnet is a simple Internet program for connecting users to remote hosts (computer systems accessible at distant locations) and servers (network devices that manage network resources). The Telnet program contains a set of procedures (commonly called a "protocol") that enables an Internet user to log on to and enter commands on a distant (remote) computer in order to simulate a user who is directly attached to the computer. Telnet, sometimes abbreviated TN, is one of the oldest activities on the Internet, being used primarily to access online databases and to read articles stored on university servers.

Telnet uses terminal emulation, a program that allows personal computers (PCs) to respond like a mainframe terminal that is connected to, and able to access, a mainframe computer or bulletin board service. (A mainframe terminal is a device consisting of a combination of keyboard and display screen that allows a user...