Perhaps the most used X11 application.

Simply a text terminal to run in a graphic terminal.

Xterm is the place where most users put their shells, such as tcsh, csh, bash or even sh.

xterms usually tend to fill your screen. The primary problem with xterm is there's so many of them. I sometimes have 20-30 xterms open. It results in heavy usage of memory, swap space, and screen realestate. I once heard you can close an xterm, but it was probably my imagination.

A terminal emulator for the X Window System that provides VT102/VT220- and Tektronix 4014-compatible terminals for programs that can't use the window system directly.