Linux Commands Cheat Sheet: Complete Reference Guide

Introduction

The Linux command line is a powerful tool for developers, system administrators, and power users. This cheat sheet provides a quick reference to the most essential Linux commands, organized by category.

Related: Master Git Commands for version control and Docker Commands for containerization.

File and Directory Management

Commands for managing files and directories.

Command	Description	Example
ls	Lists files and directories in the current directory.	ls -l
pwd	Displays the present working directory.	pwd
cd	Changes the current directory.	cd /home/user/documents
mkdir	Creates a new directory.	mkdir new_folder
rmdir	Removes an empty directory.	rmdir old_folder
rm	Removes files or directories.	rm file.txt or rm -r directory
cp	Copies files or directories.	cp source.txt destination.txt
mv	Moves or renames files or directories.	mv old_name.txt new_name.txt
touch	Creates an empty file or updates the timestamp of an existing file.	touch new_file.txt
file	Determines the file type.	file document.pdf
ln	Creates a link to a file.	ln -s /path/to/original.txt /path/to/link.txt

Archiving and Compression

Commands for archiving and compressing files.

Command	Description	Example
zip	Compresses files into a zip archive.	zip archive.zip file1.txt file2.txt
unzip	Extracts files from a zip archive.	unzip archive.zip
tar	Creates or extracts tar archives.	tar -czvf archive.tar.gz /path/to/directory

File Viewing and Editing

Commands for viewing and editing files.

Command	Description	Example
nano	A simple, modeless text editor.	nano filename.txt
vi / vim	A powerful, modal text editor.	vim filename.txt
cat	Concatenates and displays the content of files.	cat file.txt
head	Displays the beginning of a file.	head -n 10 file.txt
tail	Displays the end of a file.	tail -f /var/log/syslog

Text Processing and Searching

Commands for processing and searching text.

Command	Description	Example
grep	Searches for a pattern in a file.	grep "error" /var/log/syslog
sed	A stream editor for filtering and transforming text.	sed 's/old/new/g' file.txt
awk	A powerful pattern scanning and processing language.	awk '{print $1}' file.txt
sort	Sorts lines of text files.	sort names.txt
cut	Removes sections from each line of files.	cut -d',' -f1 data.csv
diff	Compares two files line by line.	diff file1.txt file2.txt
tee	Reads from standard input and writes to standard output and files.	`ls -l
locate	Finds files by name using a pre-built database.	locate httpd.conf
find	Searches for files in a directory hierarchy.	find /home -name "*.txt"

User and Permission Management

Commands for managing users and file permissions.

Command	Description	Example
sudo	Executes a command as another user (usually the superuser).	sudo apt-get update
su	Switches to another user account.	su - username
whoami	Displays the current username.	whoami
chmod	Changes the permissions of a file or directory.	chmod 755 script.sh
chown	Changes the owner of a file or directory.	chown user:group file.txt
useradd	Creates a new user.	useradd newuser
passwd	Changes a user's password.	passwd newuser
userdel	Deletes a user account.	userdel olduser

System Information and Monitoring

Commands for monitoring system information.

Command	Description	Example
df	Displays the amount of disk space available on the file system.	df -h
du	Estimates file and directory space usage.	du -sh /var/log
top	Displays Linux processes.	top
htop	An interactive process viewer.	htop
ps	Reports a snapshot of the current processes.	ps aux
uname	Prints system information.	uname -a
hostname	Shows or sets the system's host name.	hostname
history	Displays the command history.	history
man	Displays the on-line manual pages.	man ls

Process and Service Management

Commands for managing processes and services.

Command	Description	Example
time	Measures the execution time of a program.	time ls
systemctl	Controls the systemd system and service manager.	systemctl start apache2
watch	Executes a program periodically, showing output fullscreen.	watch -n 5 df -h
jobs	Lists active jobs.	jobs
kill	Sends a signal to a process.	kill 12345
shutdown	Shuts down or reboots the system.	shutdown -h now

Networking

Commands for networking.

Command	Description	Example
ping	Sends ICMP ECHO_REQUEST to network hosts.	ping google.com
wget	A non-interactive network downloader.	wget https://example.com/file.zip
curl	A tool to transfer data from or to a server.	curl -O https://example.com/file.zip
scp	Securely copies files between hosts on a network.	scp user@remote:/file.txt .
rsync	A fast, versatile, remote (and local) file-copying tool.	rsync -avz /local/dir user@remote:/remote/dir
ip	Shows or manipulates routing, devices, policy routing and tunnels.	ip addr show
netstat	Prints network connections, routing tables, interface statistics, etc.	netstat -tuln
traceroute	Prints the route packets trace to network host.	traceroute google.com
nslookup	Queries Internet name servers interactively.	nslookup google.com
dig	A DNS lookup utility.	dig google.com

Package Management

Commands for managing software packages.

Command	Description	Example
apt / apt-get	Package handler for Debian/Ubuntu based systems.	sudo apt-get install nginx
dnf / yum	Package manager for Fedora/RHEL based systems.	sudo dnf install httpd

Conclusion

This cheat sheet covers a wide range of essential Linux commands. Mastering these commands will significantly improve your efficiency and effectiveness when working with Linux systems.