Complete List of Bash External Commands

In the previous article, we talked about Bash environment variables and how they affect shell scripting. Now, it’s time to explore another crucial part of Linux scripting - Bash external commands .

External commands are programs that exist outside the shell itself, unlike built-in commands such as echo, test, or which. These commands are usually separate executables located in directories like /bin or /usr/bin.

They allow you to perform powerful tasks - from file management and user control to data compression, searching, and system monitoring.

What Are Bash External Commands?​

When you use a command like grep, ls, or cat, Bash doesn’t handle it internally - it actually calls an external program.
These external programs are standalone utilities installed in your system, and you can easily combine them in scripts to automate complex tasks.

For example:

grep "error" /var/log/syslog | less

Here, grep and less are external commands working together to filter and view log files efficiently.

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List of Common Bash External Commands​

Below is a handy list of the most useful Bash external commands you’ll use every day while working with Linux:

File Compression and Archiving​

• bzip2 - Compress files using the Burrows-Wheeler algorithm and Huffman coding.
• gzip - GNU’s compression tool using Lempel-Ziv compression.
• compress - The original Unix file compression utility.
• tar - Archive multiple files and directories into one single file.
• zip - Unix version of the Windows PKZIP utility.

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File and Directory Management​

• cat - Display file contents.
• cp - Copy files to another location.
• mv - Move or rename a file.
• rm - Delete a file.
• mkdir - Create a new directory.
• rmdir - Remove an empty directory.
• ls - List directory contents.
• touch - Create a new empty file or update timestamps.
• pwd - Print the current working directory.
• stat - Display detailed file information.

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User and Group Management​

• useradd - Create a new user account.
• usermod - Modify existing user details.
• userdel - Delete a user account.
• groupadd - Create a new group.
• groupmod - Modify group settings.
• chage - Set password expiration rules.
• passwd - Change a user’s password.
• chsh - Change a user’s default shell.
• chfn - Modify user info like full name or phone.
• chgrp - Change a file’s group ownership.
• chown - Change file ownership.
• chpasswd - Bulk update of user passwords.

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Disk and System Utilities​

• df - Display disk space usage.
• du - Show disk usage for directories or files.
• mount - Mount storage devices.
• umount - Unmount storage devices.
• file - Detect file type.
• finger - Display user account details.
• ps - Show running processes.
• killall - Kill processes by name.

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Searching and Text Processing​

• grep - Search files for specific patterns or text.
• sort - Sort lines of text files.
• head - Show the first few lines of a file.
• tail - Show the last few lines of a file.
• less - Advanced file viewer.
• more - Simple file viewer that pauses per screen.
• link - Create a hard link to a file.
• expr - Evaluate expressions.
• cut - Extract specific sections from text lines.

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Why External Commands Matter in Bash​

External commands are the building blocks of Linux shell scripting.
They help you:

• Automate system administration tasks
• Analyze and process large files efficiently
• Manage users, permissions, and resources easily

By mastering these commands, you’ll become a true Linux power user capable of building advanced shell scripts that save time and effort

Final Thoughts​

Whether you’re managing users, analyzing logs, or organizing data, Bash external commands are your best tools for the job.
Combine them with loops, variables, and conditionals - and you’ll unlock the full power of Linux automation