Shell scripting is a way to write programs using the command line interface (CLI) of a Unix-like operating system. A shell script is a set of instructions that a user can run to automate tasks or perform a series of commands in a batch. In this way, shell scripting is a useful tool for system administrators and power users who need to manage complex systems or perform repetitive tasks.

The shell is a program that provides a command line interface to the user. It allows users to interact with the system by entering commands, which the shell interprets and executes. The most common shell used in Unix-like operating systems is the Bash shell.

In a shell script, commands are written in a text file with a .sh extension. The first line of a shell script is called the shebang and tells the system which shell to use to execute the script. For example, #!/bin/bash tells the system to use the Bash shell.