List of Useful Linux Commands

This post contains a collection of useful Linux commands for the Ubuntu distribution. The list is extended every time I find a new handy command. Most of the commands are also applicable to other Linux distributions.

File System Commands

Description EXAMPLE
Display Current Working Directory pwd
Change Current Working Directory cd /path/to/directory
Show All Files in Current Directory (Including Hidden Ones) ls -la
Show Sizes of All Files and Directories in Current Directory du -sh *
Show Available Disk Space df -h
Copy File cp /source/file /destination/file
Move or Rename File mv /source/file /destination/file
Create Directory mkdir myDirectory
Delete File rm /path/to/file
Delete Directory Recursively rm -rf /path/to/directory
Create Symbolic Link ln -s /path/to/target /path/to/symlink
Change File Permissions sudo chmod 644 /path/to/file
Change Owner of Files / Directories (recursive) sudo chown -R user:group /my/path
Show All Disks and Partitions lsblk
Mount USB Stick pmount /dev/sdf1
Unmount USB Stick pumount /dev/sdf1
File System Commands

Viewing, Editing and Comparing Files

Description Example
Display File Contents cat /path/to/file
Edit File sudo nano /path/to/file
View End of File less +G /path/to/file
View End of File and Update Automatically tail -f /path/to/file
Compare Files in Two Directories Recursively diff -rq /path/to/dir1 /path/to/dir2
Viewing, Editing and Comparing Files

Package Management Commands

Description Example
List Upgradable Packages apt list --upgradable
Upgrade Installed Packages sudo apt upgrade
List All Installed Packages apt list --installed
Show Version of Installed Package apt list <package name>
Package Management Commands

Network / Internet / Firewall Commands

Description Example
Check Host Availability ping [IP or hostname]
Download File curl -O [URL]
List Open Ports sudo lsof -i -P -n | grep LISTEN
Open Firewall to Specific Port from Local Subnet sudo ufw allow from 192.168.1.0/24 to any port 22
Delete Firewall Rule by Number sudo ufw status numbered
sudo ufw delete 42
Network and Firewall Commands