Shell is an environment around the Kernel providing user interaction. It accepts user commands and convert them to binary code. It is not part of the kernel but uses the kernel to execute the commands.
Commonly available shells
– BASH (Bourne Again Shell)
– CSH (C Shell)
– KSH (Korn Shell)
All these shells do the same job and the differences come in the form of syntax that these shells use to execute commands and the built-in functions that comes along with it.
You can find the shell that is in execution by typing
$ echo $SHELL
To find all the available shells in the system, type
$ cat /etc/shells