Essential Linux Commands List: Usage, Examples & Explanations

Command Use Case Explanation ls List directory contents Displays files and directories in the current directory. Use ls -l for detailed info. cd Change directory Navigates between directories. Example: cd /home/user moves to /home/user. pwd Print working directory Shows the current directory path. Useful to confirm location. mkdir Create a directory Example: mkdir new_folder creates a new folder named new_folder. rmdir Remove empty directory Deletes an empty directory. Use rm -r for non-empty ones. rm Remove files or directories Deletes files (rm file.txt) or directories (rm -r folder). cp Copy files and directories Example: cp file.txt /backup/ copies file.txt to /backup/. mv Move or rename files Example: mv old.txt new.txt renames old.txt to new.txt. cat View file contents Displays file content. Example: cat file.txt. less View large files Scroll through large files page by page. Example: less log.txt. head View first lines of a file Example: head -n 10 file.txt shows the first 10 lines. tail View last lines of a file Example: tail -n 10 file.txt shows the last 10 lines. grep Search in files Example: grep 'error' log.txt searches for 'error' in log.txt. find Search for files Example: find /home -name '*.txt' finds all .txt files. locate Find files quickly Uses a prebuilt index. Example: locate file.txt. du Disk usage Example: du -sh folder/ shows folder size. df Disk space usage Example: df -h shows available disk space in human-readable format. chmod Change file permissions Example: chmod 755 script.sh sets executable permissions. chown Change file owner Example: chown user:group file.txt assigns a new owner. ps List running processes Example: ps aux shows all running processes. top Display system usage Shows CPU/memory usage and running processes. htop Interactive process viewer A better version of top (requires installation). kill Terminate a process Example: kill 1234 stops the process with PID 1234. pkill Kill process by name Example: pkill firefox terminates all firefox processes. tar Archive files Example: tar -czvf archive.tar.gz folder/ creates a compressed archive. unzip Extract ZIP files Example: unzip archive.zip. gzip Compress files Example: gzip file.txt compresses file.txt to file.txt.gz. gunzip Decompress GZIP files Example: gunzip file.txt.gz restores file.txt. ssh Secure shell connection Example: ssh user@server.com connects to a remote server. scp Secure copy over SSH Example: scp file.txt user@server:/backup/. rsync Sync files and directories Example: rsync -av source/ destination/. wget Download files Example: wget https://example.com/file.zip. curl Transfer data from URLs Example: curl -O https://example.com/file.zip. nano Edit text files Example: nano file.txt opens file.txt for editing. vim Advanced text editor Example: vim file.txt. Press i to edit, Esc to exit insert mode, :wq to save and quit. history Show command history Lists previously executed commands. clear Clear terminal screen Clears the command line screen. echo Print text to terminal Example: echo "Hello, World!". export Set environment variables Example: export PATH=$PATH:/new/path. alias Create command shortcuts Example: alias ll='ls -la' defines ll as ls -la. uptime Show system uptime Displays how long the system has been running. uname Show system information Example: uname -a displays kernel version and system details. whoami Show current user Displays the currently logged-in username. id Show user ID and group Example: id username. groups Show group memberships Lists the groups a user belongs to. passwd Change user password Example: passwd username. shutdown Power off system Example: shutdown -h now shuts down immediately. reboot Restart system Example: reboot. cron Schedule tasks Example: crontab -e opens the crontab file for scheduling tasks. systemctl Manage services Example: systemctl restart apache2 restarts Apache. journalctl View logs Example: journalctl -u apache2 shows logs for Apache. dmesg View boot logs Example: `dmesg {% raw %}ip Show network details Example: ip a displays network interfaces. ping Test network connectivity Example: ping google.com. traceroute Trace network path Example: traceroute google.com. netstat Show network connections Example: netstat -tulnp. ss Display active connections Example: ss -tulnp (alternative to netstat). nslookup Query DNS records Example: nslookup google.com. dig Get DNS info Example: dig google.com. iptables Manage firewall rules Example: iptables -L lists rules. ufw Simplified firewall Example: ufw allow 22/tcp allows SSH traffic. mount Mount file systems Example: mount /dev/sdb1 /mnt/usb. umount Unmount file systems Example: umount /mnt/usb. df Show disk usage Example: df -h. fsck Check and repair file system Example: fsck /dev/sda1. mkfs Format a filesystem Example: mkfs.ext4 /dev/sdb1. tune2fs Adjust ext4 filesystem setti

Mar 13, 2025 - 02:17

Essential Linux Commands List: Usage, Examples & Explanations

Command	Use Case	Explanation
`ls`	List directory contents	Displays files and directories in the current directory. Use `ls -l` for detailed info.
`cd`	Change directory	Navigates between directories. Example: `cd /home/user` moves to `/home/user`.
`pwd`	Print working directory	Shows the current directory path. Useful to confirm location.
`mkdir`	Create a directory	Example: `mkdir new_folder` creates a new folder named `new_folder`.
`rmdir`	Remove empty directory	Deletes an empty directory. Use `rm -r` for non-empty ones.
`rm`	Remove files or directories	Deletes files (`rm file.txt`) or directories (`rm -r folder`).
`cp`	Copy files and directories	Example: `cp file.txt /backup/` copies `file.txt` to `/backup/`.
`mv`	Move or rename files	Example: `mv old.txt new.txt` renames `old.txt` to `new.txt`.
`cat`	View file contents	Displays file content. Example: `cat file.txt`.
`less`	View large files	Scroll through large files page by page. Example: `less log.txt`.
`head`	View first lines of a file	Example: `head -n 10 file.txt` shows the first 10 lines.
`tail`	View last lines of a file	Example: `tail -n 10 file.txt` shows the last 10 lines.
`grep`	Search in files	Example: `grep 'error' log.txt` searches for 'error' in `log.txt`.
`find`	Search for files	Example: `find /home -name '*.txt'` finds all `.txt` files.
`locate`	Find files quickly	Uses a prebuilt index. Example: `locate file.txt`.
`du`	Disk usage	Example: `du -sh folder/` shows folder size.
`df`	Disk space usage	Example: `df -h` shows available disk space in human-readable format.
`chmod`	Change file permissions	Example: `chmod 755 script.sh` sets executable permissions.
`chown`	Change file owner	Example: `chown user:group file.txt` assigns a new owner.
`ps`	List running processes	Example: `ps aux` shows all running processes.
`top`	Display system usage	Shows CPU/memory usage and running processes.
`htop`	Interactive process viewer	A better version of `top` (requires installation).
`kill`	Terminate a process	Example: `kill 1234` stops the process with PID 1234.
`pkill`	Kill process by name	Example: `pkill firefox` terminates all `firefox` processes.
`tar`	Archive files	Example: `tar -czvf archive.tar.gz folder/` creates a compressed archive.
`unzip`	Extract ZIP files	Example: `unzip archive.zip`.
`gzip`	Compress files	Example: `gzip file.txt` compresses `file.txt` to `file.txt.gz`.
`gunzip`	Decompress GZIP files	Example: `gunzip file.txt.gz` restores `file.txt`.
`ssh`	Secure shell connection	Example: `ssh user@server.com` connects to a remote server.
`scp`	Secure copy over SSH	Example: `scp file.txt user@server:/backup/`.
`rsync`	Sync files and directories	Example: `rsync -av source/ destination/`.
`wget`	Download files	Example: `wget https://example.com/file.zip`.
`curl`	Transfer data from URLs	Example: `curl -O https://example.com/file.zip`.
`nano`	Edit text files	Example: `nano file.txt` opens `file.txt` for editing.
`vim`	Advanced text editor	Example: `vim file.txt`. Press `i` to edit, `Esc` to exit insert mode, `:wq` to save and quit.
`history`	Show command history	Lists previously executed commands.
`clear`	Clear terminal screen	Clears the command line screen.
`echo`	Print text to terminal	Example: `echo "Hello, World!"`.
`export`	Set environment variables	Example: `export PATH=$PATH:/new/path`.
`alias`	Create command shortcuts	Example: `alias ll='ls -la'` defines `ll` as `ls -la`.
`uptime`	Show system uptime	Displays how long the system has been running.
`uname`	Show system information	Example: `uname -a` displays kernel version and system details.
`whoami`	Show current user	Displays the currently logged-in username.
`id`	Show user ID and group	Example: `id username`.
`groups`	Show group memberships	Lists the groups a user belongs to.
`passwd`	Change user password	Example: `passwd username`.
`shutdown`	Power off system	Example: `shutdown -h now` shuts down immediately.
`reboot`	Restart system	Example: `reboot`.
`cron`	Schedule tasks	Example: `crontab -e` opens the crontab file for scheduling tasks.
`systemctl`	Manage services	Example: `systemctl restart apache2` restarts Apache.
`journalctl`	View logs	Example: `journalctl -u apache2` shows logs for Apache.
`dmesg`	View boot logs	Example: `dmesg
{% raw %}`ip`	Show network details	Example: `ip a` displays network interfaces.
`ping`	Test network connectivity	Example: `ping google.com`.
`traceroute`	Trace network path	Example: `traceroute google.com`.
`netstat`	Show network connections	Example: `netstat -tulnp`.
`ss`	Display active connections	Example: `ss -tulnp` (alternative to `netstat`).
`nslookup`	Query DNS records	Example: `nslookup google.com`.
`dig`	Get DNS info	Example: `dig google.com`.
`iptables`	Manage firewall rules	Example: `iptables -L` lists rules.
`ufw`	Simplified firewall	Example: `ufw allow 22/tcp` allows SSH traffic.
`mount`	Mount file systems	Example: `mount /dev/sdb1 /mnt/usb`.
`umount`	Unmount file systems	Example: `umount /mnt/usb`.
`df`	Show disk usage	Example: `df -h`.
`fsck`	Check and repair file system	Example: `fsck /dev/sda1`.
`mkfs`	Format a filesystem	Example: `mkfs.ext4 /dev/sdb1`.
`tune2fs`	Adjust ext4 filesystem settings	Example: `tune2fs -c 30 /dev/sda1`.
`iostat`	Show CPU and disk I/O usage	Example: `iostat`.
`vmstat`	Show system performance	Example: `vmstat 5`.
`mpstat`	Show CPU usage	Example: `mpstat -P ALL`.
`sar`	Monitor system performance	Example: `sar -u 5 10`.

This list covers essential Linux commands for daily use.