Summary  
This chapter explains how to capture and reuse the output of one command within another (command substitution) and how to produce formatted output (e.g., custom separators, colors, alignment).

General domain of usage  
System administration and automation scripting

A hands-on, beginner-friendly course to master the essentials of Bash scripting and command-line operations. Learn to navigate files, manage variables, handle input/output, and implement robust error handling—all through engaging explanations and real-world challenges.

Learn the foundational Bash commands for navigating the filesystem, listing files, and manipulating directories. Build confidence in using the terminal to interact with your computer.

Understand how to use variables in Bash scripts, including setting, referencing, and exporting environment variables for use by other programs.

Master the techniques for handling input and output in Bash, including redirection, pipes, and command substitution.

Learn how Bash uses exit codes to signal success or failure, and how to handle errors gracefully in scripts.

Command Substitution and Advanced Output