25 basic Linux commands a beginner needs to know

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Linux is one of the most popular operating systems that has been around since the mid-1990s. An operating system is a software that manages all the hardware resources in a computer or laptop. In simple terms, an operating system works the communication between your PC’s software and hardware. Therefore, if you do not have an operating system, the software would fail to function.

The Linux operating system is almost everywhere, from home desktops to organizational servers, smartphones to cars, supercomputers, and home appliances. Apart from being one of the most preferred platforms to run servers, desktops, and embedded systems throughout the globe, it is one of the highly reliable and secure operating systems.

Another significant reason why more and more people are using Linux (apart from the fact that it is free, of course) is the command line. But of course, no one is born knowing everything, and we learn as we grow and according to the needs that arise. So, worry not if you do not know where to start when using Linux commands, for this article is designed to show you the basic commands you need to know as a beginner.

Let’s acknowledge that using command lines for the first time may seem hard, but in reality, it only takes a day or two to get started with these basic commands. Understanding the command line usage is necessary for high-level coding.

Let’s start by explaining what a command line is. It is just a simple means of instructing your computer what to do. There are different ways of accessing the command line depending on the operating system in use. But of course, since we are talking about Linux commands, here is how to do so:

You can open Terminal by directly clicking “CTRL+ALT+T” or, you could choose to search it up by hitting the “Dash” icon and typing “terminal” in the search box. This will show the terminal application on the search results. Then, click on it to open.

When you launch the terminal application for the first time, an app with black background (on most occasions) will open. Once you see your username followed by a dollar sign, you are good to go, and you can now use the terminal application. If the application fails to respond, force it to shut down, restart your Linux operating system and relaunch the application.

25 basic Linux commands a beginner needs to know

Now that you are well versed about the application and how to open it on your Linux operating system, now let’s dive deep and get started with the 25 basic Linux commands that you should know:

1. pwd command

What this command does is print the location of the working directory that you are currently using. It is paramount that you know where exactly you are before heading to a parent or subdirectories.

2. Is command

ls is one of the most commonly used basic Linux commands.

It is used to print the contents of a directory. It outlines the contents of the current working directory (pwd) by default. For example: use

ls /usr/bin

This command will list the contents of the /usr/bin folder.

3. cd command

Now that we know of the pwd command and have already gotten an overview of the Is command, we shall proceed to the next, the cd command.

Example:

If you are on your home directory, to go to the /usr/local/share/fonts directory, use

cd /usr/local/share/fonts

We have three shortcuts that you could use if you want to move one directory back.

For instance, to move from the fonts directory to the share directory, run the command below:

cd ..

To head straight to your home folder  from the share directory, run the following command:

cd

if you need to go back to your last working directory (the share directory), execute the following command:

cd -

4. cat command

This command is used to print the contents of a file to the screen and create a new file.

Example:

Create a new file

create a new file called fosslinux using the command below:

cat> fosslinux

Note: If you look at the output above, you might think the command has not been executed. However, that is not the case. To check if the file has been created, check your home directory using the ls command as shown below:

ls

You can return to the home terminal window after running the cat command by clicking “CTRL+C,” as illustrated below

Check contents in a file

Since the file we created is empty, I will input the following text, “I LOVE FOSSLINUX,” and save it, then come back and check file contents using the cat command.

To check the files contained in our fosslinux file, run the following command:

cat fosslinux

Note: It is beneficial when you need to check the contents of a specific file quickly.

5. cp command

Next up, we have the cp command, which is used to copy files and directories.

Syntax:

1. cp Source Directory
2. cp Source Destination
3. cp Source-1 Source-2 Source-3 Source-n Directory

Syntax 1 and 2 are used to copy Source file to  Directory or Destination file.
Syntax 3 is used to copy multiple Source files to Directory.

Example:

I will create a new destination named fosslinuxtuts and copy files from fosslinux to it using the command below:

cp fosslinux fosslinuxtuts

Let’s look at the newly created file and its content using the previously covered commands: ls and cat commands.

Note: Remember to use the proper path when copying files and directories from one place to another on your Linux operating system to avoid causing errors.

6. mv command

This command is used to move or rename directories and files. If you need to rename a file, use mv old_name new_name

Example:

mv fosslinux foss_linux_tuts

Use the ls and cat command to check changes made to the file as shown:

7. rm command

The rm command is used to remove directories or files. You can use rm -r /foss_linux_tuts to remove the file.

Check if the file has been removed using the ls command

Note: You have to take caution before removing any file or directory since a slight mistake might cause you nightmares.

8. mkdir command

The mkdir command is used when you want to make a new directory in Linux. To create a new directory, run the command below:

mkdir fosslinux

The above command creates a new directory named fosslinux.

Note: You can also use the -p argument to avoid making the parent directories manually.

9. rmdir command

This command is used when you want to remove a directory. For example, use the following command to remove the fosslinux directory we created in the previous step using the mkdir command. Next, use the ls command to check if the directory has been removed

rmdir fosslinux

10. touch command.

touch is a command that is somewhat similar to mkdir, but it is used for files. With the touch command, you can create a blank file. For example, use the following command to make a blank index.html file under the Foss directory.

 touch ~/Foss/index.html

Note: ensure before running the above command, first create a directory. For instance, in our case, we shall make a directory named Foss by using the mkdir command covered previously.

11. ln command

Next up, we have the ln command, which can create links between files and directories. For example, let’s assume you want a symbolic link on the /var/www directory stored on the /tmp directory. Here is what you use:

ln -s /var/www/ /tmp/

Let’s now assume you now want to un-link that symlink. You should use:

 unlink /tmp/www

Please note that you must be very careful when providing the complete path and trailing slashes during linking and unlinking processes.

12. sudo command

This command can be said to be an essential yet potentially dangerous command. It is used when you get a “permission denied,” “authorization failed,” or something that requires administrator privileges.

For instance, the /var/www cannot be written on by the usual user. Now, for you to create a blank index.html file under the /var/www directory, use:

 sudo touch /var/www/index.html

13. head command

If you want to print the first couple of lines in any file, the head command comes into play. An excellent practical example would be:

head -15 /var/log/syslog

This will print the first 15 lines of the rsyslogd log.

Note: By default, the Head command prints the first 10 lines.

14. tail command

This command is similar to the head command, but the difference is that it functions differently. This command prints the last lines of any file compared to the head command that prints the first line in a file. By default, it prints the last 10 lines of any file. The following is an example of how to print the last 25 lines of the kernel log:

tail -25 /var/log/kern.log

15. chmod command

This is also an essential command that is used to change file and directory permission. There are three types of permission. These are; read, write and execute permissions, and a number denotes every single one of them

• 4 for read permission
• 1 for execute permission
• 2 for write permission

If you want to set universal read/write permission to a file, you can use:

chmod 666 fosslinux

and if you want to make a script executable, you can use:

 chmod +x fosslinux

16. md5sum command

You may need to check whether a file is tampered with or not. In that case, you can use:

md5sum fosslinuxtuts

However, it is not very secure even though it is used a lot.

Note: the md5sum command cannot be used on a directory. Therefore, if you don’t have a file, refer to the previously covered commands to create a new file if you lack one.

17. locate command

This is the basic command to find directories and files in Linux. Given that it is a command-driven by the database, run sudo updatedb for the first time. Remember to build the database and wait for a few minutes.

Here is an example to locate an application:

 locate -i *chrome*

It supports wildcards, and you can use the -i option to ignore the lower and upper case.

Note: In most Linux operating systems, the locate command has not been installed. therefore, to install it, run the following command:

sudo apt-get install locate

18. df command

The df command is used to check the space used in a disk on a Linux system. The most common usage is as follows, used along with the -h flag:

df -h

19. du command

The du command is handy when you need to have a quick look at the disk space usage of a directory or a file.

Here is an example for a single file:

sudo du -sh Foss

And here is another one for an entire directory and its contents:

du -sh /opt/google/chrome/

The -s flag is used to repress unnecessary clutter, and the -h flag makes the output more understandable by the person using or running the command.

Note: if you run the du commands and find the “permission denied” error, use the “sudo” command.

20. free command

This command displays the amount of used and free RAM in the system. For example, to check the free RAM on our PC, run the following command:

free -h

Note: as we have seen in the above command, the -h flag here is also used to make the output more readable and understandable.

21. zip command

You will come across situations where you will need to create and extract zip archives. Below is the zip and unzip commands to do so:

sudo apt-get install zip unzip

While here is the syntax to create a zip archive:

zip -9r my_archive.zip . -i file_1 file_2 folder_1 folder_2 folder_3

The -9 option is used to attempt maximum compression on all files, and the -r option is for recursive archiving.

Now, the unzip command extracts archives to the current working directory
(pwd) by default. So, if you want to extract the contents to a specific folder, use: unzip my_archive.zip -d /path/to/my_directory

22. ifconfig command

ifconfig in complete means interface configuration, and it carries out a lot of networking-related tasks. As a beginner, you could check which network interfaces are connected and their respective IP address or use it to check the amount of data passed through a specific interface. This can all be executed by running the following command:

 ifconfig -a

Note: It is probable that these commands are not pre-installed, so you should install them with apt in Ubuntu. for instance, you can install the ifconfig command using the command below:

sudo apt install net-tools

23. uname command

uname command is used to print some basic information about the system such as; the hostname, kernel version, OS name, system time, OS architecture, and much more:

uname -a

24. history command

This command prints a list of previously typed commands by clicking on the CTRL+R key combination.

It is instrumental when you are trying to know the commands previously executed. to show the history, run the command below:

history

25. man command

This is the command to use when you want to find details about other commands. Most commands have their respective man pages used to get a quick overview of an unknown command. Use it like this: man any_command

Example:

man ifconfig

Conclusion

When working on Linux operating systems, you should familiarize yourself with the basic Linux commands that you will encounter while working with this operating system. Therefore, we hope we provided a factual background on basic Linux commands to kickstart your Linux journey. Please note that some of the mentioned commands are not pre-installed on your Linux operating system, and hence to use them, you will have to go an extra mile of installing them using the apt command.

We believe you can now run some basic commands and understand what it does on your computer. With the aid of examples, the article clearly explains the basic Linux commands any beginner should familiarize themselves with. We hope you find the article yes, and if yes, please don’t forget to give a thumbs up via the comments section. Thanks for reading.