Linux commands that every developer should know, along with a brief description and an example of each command:
| Command | Explanation | example |
|---|---|---|
ls |
Lists the contents of a directory. | ls will list the contents of the current directory. ls /usr/local will list the contents of the /usr/local directory. |
pwd |
Prints the current working directory. | pwd will print the full path of the current working directory. |
cd |
Changes the current working directory. | cd /usr/local will change the current working directory to /usr/local. |
mkdir |
Creates a new directory. | mkdir mydir will create a new directory called mydir. |
mv |
Moves a file or directory. | mv file.txt /usr/local/ will move the file file.txt to the /usr/local directory. |
cp |
Copies a file or directory. | cp file.txt /usr/local/ will copy the file file.txt to the /usr/local directory. |
rm |
Removes a file or directory. | rm file.txt will remove the file file.txt, while rm -r mydir will remove the directory mydir and all of its contents. |
touch |
Creates a new empty file. | touch file.txt will create a new empty file called file.txt. |
ln |
Creates a link to a file or directory. | ln -s /usr/local/file.txt file.txt will create a symbolic link to /usr/local/file.txt called file.txt in the current directory. |
cat |
Displays the contents of a file. | cat file.txt will display the contents of the file file.txt in the terminal. |
clear |
Clears the terminal screen. | clear will clear the contents of the terminal screen. |
echo |
Prints a message to the terminal. | echo "Hello, world!" will print the message "Hello, world!" to the terminal. |
less |
Views a file with pagination. | less file.txt will allow you to view the contents of file.txt one page at a time. |
man |
Displays the manual page for a command. | man ls will display the manual page for the ls command, which describes its usage and options. |
uname |
Displays information about the current system. | uname -a will display all information about the current system, including the kernel version and machine hardware name. |
whoami |
Displays the current user. | whoami will display the username of the current user. |
tar |
Archives and compresses files and directories. | tar -czf archive.tar.gz directory/ will create a compressed archive called archive.tar.gz from the contents of the directory directory. |
grep |
Searches for a pattern in a file. | grep "error" log.txt will search the file log.txt for the pattern "error" and print any lines that match. |
head |
Displays the first few lines of a file. | head -n 10 file.txt will display the first 10 lines of file.txt. |
tail |
Displays the last few lines of a file. | tail -n 10 file.txt will display the last 10 lines of file.txt. |
diff |
Compares the differences between two files. | diff file1.txt file2.txt will compare the contents of file1.txt and file2.txt and print the differences between them. |
cmp |
Compares the contents of two files byte by byte. | cmp file1.txt file2.txt will compare the contents of file1.txt and file2.txt byte by byte and report any differences. |
comm |
Compares the contents of two sorted files line by line. | comm file1.txt file2.txt will compare the contents of file1.txt and file2.txt, which should both be sorted, and print the lines that are unique to each file. |
sort |
Sorts the lines of a file. | sort file.txt will sort the lines of file.txt alphabetically. |
export |
Exports a shell variable. | export VARNAME="value" will create a shell variable called VARNAME with the value "value". |
zip |
Compresses files into a ZIP archive. | zip archive.zip file1.txt file2.txt will create a ZIP archive called archive.zip containing the files file1.txt and file2.txt. |
unzip |
Extracts files from a ZIP archive. | unzip archive.zip will extract the contents of the archive.zip ZIP archive. |
ssh |
Connects to a remote server using the SSH protocol. | ssh [email protected] will connect to the server at example.com as the user user. |
service |
Controls system services. | service apache2 start will start the Apache web server. |
ps |
Displays information about running processes. | ps aux will display a list of all running processes and their resource usage. |
kill |
Sends a signal to a process to terminate it. | kill 12345 will send the signal to terminate the process with the process ID 12345. |
killall |
Terminates all processes with a specified name | killall firefox will terminate all processes with the name firefox. |
df |
Displays information about available disk space on mounted filesystems. | df -h will display the available disk space in a human-readable format (e.g., in gigabytes or megabytes). |
mount |
Mounts a filesystem. | mount /dev/sda1 /mnt/mydisk will mount the partition /dev/sda1 at the mount point /mnt/mydisk. |
chmod |
Changes the permissions of a file or directory. | chmod 755 file.txt will give read, write, and execute permissions to the owner and read and execute permissions to everyone else for the file file.txt. |
chown |
Changes the ownership of a file or directory. | chown user:group file.txt will change the owner of file.txt to user and the group ownership to group. |
ifconfig |
Configures network interface parameters. | ifconfig eth0 up will enable the network interface eth0. |
traceroute |
Traces the path of packets to a destination. | traceroute example.com will trace the path of packets from the current system to the destination example.com. |
wget |
Downloads a file from the internet. | wget https://example.com/file.zip will download the file file.zip from https://example.com. |
ufw |
A frontend for managing a firewall. | ufw allow ssh will allow incoming connections to the SSH service. |
iptables |
A firewall management tool for Linux. | iptables -A INPUT -p tcp --dport 80 -j ACCEPT will allow incoming connections to TCP port 80 (the default port for HTTP). |
apt |
A package manager for Debian-based systems. | apt update will update the list of available packages. |
sudo |
Allows a user to run a command with the privileges of the superuser (root). | sudo apt update will update the list of available packages with root privileges. |
cal |
Displays a calendar. | cal will display the current month's calendar. |
alias |
Creates an alias for a command. | alias ll='ls -alF' will create an alias ll that runs the command ls -alF. |
dd |
Copies data from one location to another. | dd if=/dev/sda of=disk.img will create an image file called disk.img of the contents of the device /dev/sda. |
whereis |
Shows the locations of a command. | whereis ls will show the locations of the ls command on the system. |
whatis |
Shows a short description of a command. | whatis ls will show a short description of the ls command. |
top |
Displays information about running processes. | top will display a list of running processes and their resource usage in real-time. |
passwd |
Changes the password for a user. | passwd user1 will prompt you to enter and confirm a new password for the user user1. |
More details about a specific command can be found by following the link below:
- Bash URL:
https://linux.die.net/man/1/change_command_name