Linux Commands Cheat Sheet

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`.

Reference

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