WHAT IS SHELL SCRIPT ?

What is SHELL Script ?

Normally shells are interactive . It means shell accept command from us and execute them. But if
you use command one by one , then you can store the sequence of command to text file and tell
the shell to execute this text file instead of entering the commands. This is known as shell script.
Shell script defined as :
"Shell script is a series of commands written in plain text file. Shell script is just like a
batch file in MS-DOC but have more power than the MS-DOC batch file."

Why to write shell script ?

>> useful to create our own commands.
>> shell script can take i/p from user and o/p them on screen
>> save lots of time.
>> To automate some task of day today life.
>> System Administration part can be also automated.