From GTALUG

Bash

Wikipedia:Bash is a Unix shell written for the GNU Project. The name of the actual executable is bash. Its name is an acronym for Bourne-again shell, a pun ('Bourne again' / 'born again') on the name of the Bourne shell (sh), an early and important Unix shell written by Stephen Bourne.

Almost all Linux distributions use Bash as the base user "shell".

It used to be that nearly all Linux distributions would use Bash as the shell underpinning the base init process; that is becoming no longer the case.

• Embedded systems, starved for space, often use wikipedia:Busybox
• A number of Debian derivatives use wikipedia:Debian_Almquist_shell, primarily because it is somewhat faster and smaller than Bash.