Terminal emulator

A terminal emulator, terminal application, or term for short, is a program that emulates a "dumb" video terminal within some other display architecture. (The use of the word "emulator" here does not carry any software piracy connotations.)

A terminal emulator inside a graphical user interface is often called a terminal window. A terminal window usually supports a telnet, ssh[?], or dial-up shell session to a remote system that offers either a command line interface (such as a Unix shell) or to a character-cell application based. The original character mode terminal applications typically provided a connection via modem to a BBS.

Example programs that provide this capability under Microsoft Windows include the built-in programs HyperTerminal and Telnet.exe, 3rd party programs like Putty (http://www.chiark.greenend.org.uk/~sgtatham/putty/), SSH Secure Shell, SecureCRT, and (insert your favorite terminal client here).

In the UNIX based environment, the CLI is the foundation of all life and there are numerous programs for providing access back to it from the X Window System GUI. The most mature of the bunch are xterm and rxvt.