| Command | Meaning |
|---|---|
apt |
Advanced Package Tool – installs, updates, removes packages |
apt update |
Updates the package list from repositories |
apt upgrade |
Installs available updates for installed packages |
apt install <package> |
Installs a new package |
apt remove <package> |
Removes an installed package |
dpkg -i |
Installs a .deb file manually |
| Command | Meaning |
|---|---|
adduser <username> |
Adds a new user (friendly version) |
useradd <username> |
Adds a user (low-level command) |
passwd <username> |
Sets or changes password for a user |
usermod -aG sudo <username> |
Adds user to sudo group (admin access) |
id <username> |
Shows UID, GID, and groups of a user |
who / w |
Shows who is logged in |
| Command | Meaning |
|---|---|
chmod |
Changes file permissions (rwx) |
chown |
Changes file owner or group |
ls -l |
Shows permissions and ownership |
umask |
Sets default permissions for new files |
| Command | Meaning |
|---|---|
ls |
Lists files |
cd |
Changes directory |
pwd |
Shows current directory |
cp |
Copies files or folders |
mv |
Moves or renames files |
rm |
Deletes files or folders |
touch |
Creates an empty file |
mkdir |
Creates a directory |
cat |
Displays file contents |
nano / vi |
Terminal-based text editors |
| Command | Meaning |
|---|---|
find |
Finds files by name, type, size, etc. |
grep |
Searches inside files |
less / more |
Scroll through file contents |
head / tail |
Show first or last lines of a file |
| Command | Meaning |
|---|---|
top / htop |
Shows live system processes and resource usage |
df -h |
Shows disk space usage |
du -sh <folder> |
Shows size of a folder |
free -h |
Shows memory usage |
uptime |
Shows how long the system has been running |
reboot / shutdown |
Restarts or shuts down the system |