Secure Shell - Connect to remote Linux machines securely over a network.
ssh user@192.168.1.100
Remote Access
List directory contents - shows files and directories in current location.
ls -la # List all including hidden files
File Management
Print Working Directory - shows the current directory path.
pwd
Navigation
Change Directory - navigate between folders.
cd /home/user/Documents
Navigation
Create new empty files or update file timestamps.
touch newfile.txt
File Management
Display message or add content to files.
echo "Hello" >> file.txt
Text Processing
Simple text editor for terminal-based file editing.
nano file.txt
Editors
Powerful terminal-based text editor with advanced features.
vim file.txt
Editors
Concatenate and display file contents quickly.
cat file.txt
Text Processing
Securely delete files by overwriting their contents.
shred -u secret.txt
Security
Create new directories/folders.
mkdir new_folder
File Management
Copy files and directories.
cp file.txt /backup/
File Management
Move or rename files and directories.
mv old.txt new.txt
File Management
Remove files or directories (use with caution).
rm -r old_directory/
File Management
Remove empty directories.
rmdir empty_folder/
File Management
Create links between files (symbolic or hard links).
ln -s target.txt link.txt
File Management
Clear terminal screen.
clear
Terminal
Display current username.
whoami
System Info
Execute commands with superuser privileges.
sudo apt update
Administration
Create new user accounts (requires sudo).
sudo useradd newuser
User Management
Interactive user creation with more options.
sudo adduser newuser
User Management
Switch user accounts.
su - otheruser
User Management
Exit current shell or user session.
exit
Terminal
Change user password.
passwd
Security
Display manual pages for commands.
man ls
Help
Brief description of a command.
whatis ls
Help
Show full path of commands.
which python
Help
Download files from the internet.
wget https://example.com/file.zip
Networking
Transfer data to/from servers (more features than wget).
curl -O https://example.com/file.zip
Networking
Compress files into a zip archive.
zip archive.zip file1.txt file2.txt
Compression
Extract files from a zip archive.
unzip archive.zip
Compression
View file contents page by page.
less longfile.txt
Text Processing
Display first lines of a file.
head -n 10 file.txt
Text Processing
Display last lines of a file (often used with -f for logs).
tail -f /var/log/syslog
Text Processing
Compare two files byte by byte.
cmp file1.txt file2.txt
Text Processing
Show differences between two files.
diff file1.txt file2.txt
Text Processing
Sort lines of text files alphabetically.
cat file.txt | sort
Text Processing
Search for files in a directory hierarchy.
find /home -name "*.txt"
File Management
Change file permissions.
chmod +x script.sh
Permissions
Change file owner and group.
chown user:group file.txt
Permissions
Display network interface configuration (deprecated on some systems).
ifconfig
Networking
Modern replacement for ifconfig with more features.
ip address show
Networking
Search text using patterns (extremely powerful).
grep "error" /var/log/syslog
Text Processing
Pattern scanning and text processing language.
awk '{print $1}' file.txt
Text Processing
Test network connectivity to a host.
ping google.com
Networking
Trace the network path to a host.
traceroute google.com
Networking
Display network connections, routing tables, and interface statistics.
netstat -tulpn
Networking
Modern replacement for netstat.
ss -tulpn
Networking
Uncomplicated Firewall - simplified interface for iptables.
sudo ufw allow 22/tcp
Security
Print system information.
uname -a
System Info
Display amount of free and used memory.
free -h
System Info
Show disk space usage.
df -h
System Info
Report current processes.
ps aux
Processes
Display Linux processes in real-time.
top
Processes
Terminate processes by ID.
kill -9 1234
Processes
Terminate processes by name.
pkill -f "process_name"
Processes
Control systemd system and service manager.
sudo systemctl restart nginx
Services
Display command history.
history
Terminal
Shut down or reboot the system.
sudo shutdown -h now
System