Linux Commands
Command references for core Linux tools, syntax, examples, and practical one-liners.
export Command in Linux: Set Bash Environment Variables
Use export to turn Bash shell variables into environment variables that child processes inherit, list exported variables, and make them permanent across sessions.
mv Command in Linux: Move Files and Directories
Move and rename files and directories in Linux with the mv command, including overwrite prompts, backups, the -T option, and cross-filesystem moves.
git stash: Save and Restore Uncommitted Changes
Use git stash to set aside uncommitted changes, switch branches, and bring the work back later. Includes applying a specific stash, stashing untracked files, and fixing pop conflicts.
Linux File Permissions Explained
Linux file permissions control who can read, write, and execute files and directories. Learn how to inspect and change permissions with ls, stat, and chmod.
chmod 777: What It Means and Why You Should Never Use It
chmod 777 grants every user full control of a file or directory. See why it is risky and when to use safer 755 or 644 permissions instead.
How to Unzip a .gz File in Linux
Unzip a .gz file in Linux with gzip or gunzip, keep the original file when needed, and extract .tar.gz archives with tar.
id Command in Linux: Display User and Group Information
Use the id command to print a user's UID, GID, and group memberships, get single values for shell scripts, and see why a newly added group does not show up yet.
How to Use the pkill Command in Linux
The pkill command sends signals to Linux processes by name, user, terminal, or full command pattern. Covers safe matching, common options, and examples.
pgrep Command in Linux: Find and Filter Running Processes
The pgrep command finds running processes by regex pattern, user, terminal, or parent PID and prints matching PIDs. This guide covers exact matching, filtering options, and script-friendly exit checks.
ssh Command in Linux: Connect to Remote Servers
The ssh command connects you to a remote Linux server. This guide covers its syntax, the most useful options, key-based login, and port forwarding.
less Command in Linux: Navigate and Search Files
How to use the less command in Linux to view files page by page, search for text, follow log files in real time, and navigate with vi-style key bindings.
How to Find Which Process Is Using a Port in Linux
Find the Linux process listening on a TCP or UDP port with ss, lsof, fuser, or netstat, then inspect and stop it safely.
How to Unzip Files in Linux
Extract ZIP archives in Linux with the unzip command: unzip to a folder, handle password-protected and multiple archives, list or test contents, and exclude files.
zip Command in Linux: Zip Files and Directories
Create ZIP archives in Linux with the zip command. Zip directories recursively, exclude files, add a password, and split large archives.
jq Command: Process JSON from the Terminal
How to use the jq command to read, filter, and transform JSON on the command line, from selecting fields to building new objects and parsing API responses.
passwd Command in Linux: Change User Passwords
Change your own, another user's, or the root password in Linux with the passwd command. Covers password expiry with chage, forcing a change at next login, and account locking.
Linux Folder Size: How to Check File and Directory Sizes
Check folder and file sizes in Linux with du. Compare directory totals, rank subdirectories, exclude paths, and check free space with df.
