1. Introduction

Shell Script

  • A shell script is a text file containing executable commands.
  • Scripts can automate repetitive tasks and change behavior based on conditions.

Example of a simple script:

echo "Hello, World!"
Run a script with:

sh script.sh      # via shell
./script.sh       # directly (needs execute permission)

Shebang (#!) specifies the interpreter for the script

#!/bin/bash
echo "Hello, World!"
* Shebang works for shells and other scripting languages (Python, Perl, Ruby). * Always create scripts in plain text, not formatted office documents.