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Bash lessons (5/29)

Bash — Comments

Single-line comments

#!/bin/bash

# This is a comment
echo "Hello" # Inline comment

Multi-line comments

#!/bin/bash

: '
This is a multi-line comment.
It spans multiple lines.
Useful for longer explanations.
'

echo "Hello"

Documenting scripts

#!/bin/bash
# Script: hello.sh
# Author: Your Name
# Date: 2026-08-23
# Description: Prints a greeting message
# Usage: ./hello.sh [name]

echo "Hello, ${1:-World}!"

When to comment

  • Explain why something is done
  • Document script purpose and usage
  • Mark TODOs and FIXMEs
  • Don't comment obvious code

Mini Practice

Write Bash code that:

  1. Uses # comments to explain variables
  2. Uses : '...' for multi-line comments
  3. Documents a script with header comments

Up Next

In the next lesson, you'll learn about Variables — declaring and using variables in Bash.

Related Topics

Frequently Asked Questions about Comments

What is Comments in Bash?

Comments is a fundamental concept in Bash. This lesson explains it step by step with clear examples, making it easy for beginners to understand.

How do I learn Comments?

Start by reading the explanation above, then try the code examples. Practice by modifying the examples and experimenting with different values. Hands-on practice is the best way to learn Comments.

Why is Comments important in Bash?

Comments is essential for Bash development. Understanding this concept will help you write better code and solve real-world problems more effectively.