I normally use the bash shell
on Unix and Linux systems. A shell is the user interface to the system.
The shell on Unix and Linux systems gives you the type of interface
you get with a command prompt on Windows systems. On older versions of
Windows you would be issuing DOS commands at the command prompt. As you
have batch files with DOS, with Unix and Linux shells you can create
scripts to automate your work, though you normally get a much richer
set of commands than with DOS.
Prior to the development of the bash shell there was a Bourne shell and
the name Bourne Again Shell (bash) comes from the name of that prior shell. The bash shell was created by Brian Fox in 1988. He continued to work on it until
1993. Chet Ramey joined Brian in the development of bash in 1989 and Chet
continued the work on bash after Brian ceased his development efforts on bash.
I've posted a few bash tips in Bash