Linux is an open-source operating system with a huge number of distributions, some of them:
Most of these operating systems have a graphical interface that provides a wealth of features, but the greatest power of Linux comes with the use of a command-line interface (CLI)
For this reason, it is useful to know some of the most common Linux CLI commands.
Commands for working with files
Many times, we can change the active directory we are currently working with. This is done with the
cd /home/user/folder1 # Current directory will be /home/user/folder1
ls command is used to display the contents of the current directory.
ls # Output example Desktop Documents Downloads Music Public Temp .gitconfig ls -R # list all the files in the sub-directories ls -a # show hidden files ls -al # list all info's about a file (size, owner ...)
The command tells us which is the currently active directory.
pwd # return the current directory # output example /home/user/folder1
Perhaps the most commonly used command in Linux, as it allows you to create, combine files.
cat > file # create file with name file in current directory cat file1 file2 > file3 # joins file1 and file2 and create output file3 in current directory
cp command disables copying a file from the current directory to another.
cp document.txt /home/user/Documents # copy document.txt from current directory to folder called Documents
mv allows you to move files.
mv document.txt / home / username / Documents # move document.txt from current directory to folder called Documents
You can also rename files with this command.
mv oldname.txt newname.txt # rename file from oldname.txt to newname.txt in the current directory
This command creates new folders.
mkdir Archive / Documents # create folder called Documents from current directory mkdir -p Archive / 2021 / Documents # create folder 2021 between folders Archive and Documents
Commands can be used to delete folders.
With rmdir we can only delete empty folders.
With rm, you can delete the entire folder (check before use because it is not possible to restore the deletion).
rmdir NotusefulFolder # remove NotusefullFolder (it is empty) from the current directory rm Folders / NotInUse # remove all files and folders in folder NotInUse from the current directory rm -r NotUsefulFolder # command equal to rmdir
The command allows you to create new files.
touch file.txt # create a file in the current directory
Used to search for a specific file.
This command allows us to print the contents of a file.
Display us the first 10 lines of the file.
Return filesystem directory tree.
Abbreviation for "SuperUser Do", with this command we can execute commands that require administrative authority.
sudo <SOME_ACTION> # In the next step you must input the password for the root/admin user
Shows us disk usage in KB and percent.
df # Return disk usage in KB df -m # Return disk usage in MB
The Kill command allows you to stop a specific process.
ps # return list of active processes kill 11111 #kill process with PID 11111
They allow us to create compressed zip files and expand zip files.
unzip zipped_file.zip # command unzip zipped_file.zip file
The command is used in most cases when we want to check if a device is active on the network
The command tells us the name of the device
hostname # return hostname of the device # example output server
useradd allows us to create a new user. Passwd allows us to change or set a password.
useradd NewUserName # create new user userdel UserName # delete user passwd UserName # can set a password if doesn't exist or change if exists
A very useful command to download files.
wget DownloadFileURL # download file in current directory
After giving us the amount of memory used.
free -h # return usage of memory - RAM (human-friendly numbers and units)
Simple commands - the sessions already name what they learn.
shutdown # shutdown computer reboot # reboot computer
Maybe if you have read in detail and gotten to know the Windows terminal, then you have noticed some commands are the same.
Of course, there are even more of these commands, but I mentioned the most commonly used ones. If I forgot any, and you find it important to use in Linux, mention them in the comments 😊.