What is shell scripting?

Question

=> What is it?
=> How many types?
=> Why is it used for?
=> any other thing you know how to learn and other!

Answer 1

as told by martin and Chris I ll just add few stuffs

it's called powershell in Windows,

in Ubuntu I often use shell scripts to bundle few repetitive commands that I use very often in a single shell script ,

it's very fun to play with , give it some time , very simple syntax too , you ll be able to do awesome automation stuffs with it considering you have good knowledge of few commands in Linux ,

for Ubuntu many times when I download any app, then I look for a .sh file , that contains the commands written into a single file, that otherwise I d have to type manually into my command line one after other

Answer 2

It's for automating stuff you'd otherwise have to do with multiple steps in the shell/terminal.
You just create a .sh-file and write the shell commands (cd, ls, grep, rm, whatever) into it and execute it via the terminal.

Answer 3

so I read few forums, that bash is the most popular hence but has large memory footprint too, which is not preferred in few places,

random fact :
bash stands for Bourne again shell , someone said that he still uses Bourne shell just because then his scripts would run on any Linux variant