There are many tools in linux for command executions and one of them is called the “shell programming”.

The most common Linux shell is named “Bash” is the default shell on linux. The name comes from “Bourne Again SHell” ,written by Brian Fox.

As it is the default shell of linux so people prefer using it than any other shells as it makes them to use it worldwide as it now becomes machine independent and operating system independent.

There are two ways to use the shell: interactively and by writing shell scripts( known as shell scripting ).

* In the interactive mode, the user types a single command or a short string of commands and the result is printed out on the screen.

*In shell scripting, the user types anything from a few commands  to an entire program( collection of programs) into a text editor, then executes the resulting text file as a shell script.