A shell in a Linux operating system takes input from you in the form of commands, processes it, and then gives an output. It is the interface through which a user works on the programs, commands and scripts. A shell is accessed by a terminal which runs it.

When you run the terminal, the Shell issues a command prompt, where you can type your input, which is then executed when you hit the Enter key. The output or the result is thereafter displayed on the terminal.

The Shell wraps around the delicate interior of an Operating system protecting it from accidental damage. Hence the name Shell.

Writing a series of command for the shell to execute is called shell scripting.It can combine lengthy and repetitive sequences of commands into a single and simple script, which can be stored and executed anytime. This reduces the effort required by the end user..

Here we are going to cover
1. Basics of Shell Scripting
2. Complex Shell scripting for data processing
3. AWK and sED Commands