9 Useful Basic Unix Commands

3 min readFeb 6, 2023

This article is targeted at people who are new to Unix & want to learn its most-used commands that are used in the terminal.

cd

cd ~/Projects

Unless you’re new to unix, I think everybody knows what this do. This commands will change your current terminal’s directory to another directory. For example, if you’re in a directory and you want to change to b directory, simply type cd b. More complete explanation: link.

ls

ls

This command will list what files/folders you have in your current directory. To also view all hidden files/folders, type ls -a .

mv

mv ./a.txt ./b.txt

This command can either move a file to another directory, or, like above, rename a file. The first argument (a.txt) is the file while the second argument is the new file name (in case of renaming) or the directory (in case of moving a file). To move to a directory (say, b directory), you can type mv a.txt b/ .

rm

rm ./a.txt

This command is used for removing a file. If you want to remove a folder, use rm -rf [folder_name] .

mkdir

mkdir app

This command is used to create a new directory. You can create nested directory by using mkdir -p a/b/c .

cat

cat ./a.txt

Unlike its names, cat is used to show the content of a file. There are more uses of this command, but you can learn as you go.

ps -e

ps -e

This command is used to list processes currently running on the machine. If this command doesn’t work, try calling sudo ps -e (you will learn more about sudo)

Mostly you only look at “PID” and “CMD” from the output.

kill -9

kill -9 [PID]

Like its name, kill -9 is used to remove a running process. You can get the PID from the process above.

grep

[some_command] | grep search_value

Grep is used to filter out results of a command. I can type ls | grep Doc If I to get any file/folders in current directory that have “Doc” in it. grep can be used with many command, as long as you place it after the | character.