Introduction to Bash

Bash (Bourne Again SHell) is a command-line interpreter that is widely available on Linux and macOS. It is the default shell for many Linux distributions and provides a command-line interface for users to interact with the operating system.

Key Features:

• Command History
• Job Control
• Shell Functions and Aliases
• Command Line Editing

Common Commands

• ls - Lists files and directories in the current directory.
• cd - Changes the current directory.
• pwd - Prints the current working directory.
• mkdir - Creates a new directory.
• rm - Removes files or directories.

Examples

# List files
ls -l

# Change to home directory
cd ~

# Create a new directory named 'test'
mkdir test

# Remove a file named 'file.txt'
rm file.txt
                

Bash scripting allows you to automate tasks by writing a series of commands in a file. Here is a simple example:

#!/bin/bash
# This is a simple script

echo "Hello, World!"
                

To run the script, you need to:

1. Save the script in a file, e.g., hello.sh.
2. Make it executable: chmod +x hello.sh.
3. Run the script: ./hello.sh.

When writing Bash scripts, consider these best practices:

• Use comments to explain your code.
• Use meaningful variable names.
• Check for errors after executing commands.
• Keep your scripts modular and reusable.