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Hey guys in this article, I will write the most important commands for a newbie Linux user. Read the article completely to learn about Linux basic commands.

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Terminal Emulators

The above is the screenshot of the Gnome terminal application. As you can see the command prompt contains the following information:

[username@hostname directoryname]

In our case the username is bushansirgur, hostname is Bushans-MacBook-Air, and directory is mentioned as ~. This ~ is a special character in our case. It means the home directory of the user. In our case, the home directory path is /home/bushansirgur/.

The Gnome terminal is one of many implementations of terminal emulators. Different Linux environments may come pre-installed with different terminals.

date command

date command prints the current date time.

$ date
Sun Jan 01 09:00:10 IST 2023

In case you want to know the current date/time in UTC, use the following command.

$ date -u
Sun Jan  1 13:30:53 UTC 2023

cal command

cal command is used to display a calendar in your shell, by default it will display the current month

$ cal
    January 2023      
Su Mo Tu We Th Fr Sa  
 1  2  3  4  5  6  7  
 8  9 10 11 12 13 14  
15 16 17 18 19 20 21  
22 23 24 25 26 27 28  
29 30 31              

$ cal 02 2023
   February 2023      
Su Mo Tu We Th Fr Sa  
          1  2  3  4  
 5  6  7  8  9 10 11  
12 13 14 15 16 17 18  
19 20 21 22 23 24 25  
26 27 28              

whoami command

whoami command will tell you which user account you are using in this system.

$ whoami
bushansirgur

id command

id prints real user id, and various other details related to the account.

$ id
uid=501(bushansirgur) gid=20(staff) groups=20(staff),12(everyone),61(localaccounts),79(_appserverusr),80(admin),81(_appserveradm),98(_lpadmin),702(com.apple.sharepoint.group.2),33(_appstore),100(_lpoperator),204(_developer),250(_analyticsusers),395(com.apple.access_ftp),398(com.apple.access_screensharing),399(com.apple.access_ssh),400(com.apple.access_remote_ae),701(com.apple.sharepoint.group.1)

pwd command

pwd command, short for the print working directory, will help you to find out the absolute path of the current directory.

$ pwd
/Users/bushansirgur

cd command

The next command we will learn is cd, short for change directory. This command will help you to change your current directory. We will move to Documents/ directory in our example

bushansirgur@Bushans-MacBook-Air ~ % cd Documents 
bushansirgur@Bushans-MacBook-Air Documents % pwd
/Users/bushansirgur/Documents
bushansirgur@Bushans-MacBook-Air Documents % cd ~
bushansirgur@Bushans-MacBook-Air ~ % pwd
/Users/bushansirgur

Here you can see that first, we moved to Documents/ directory, and then we moved back to the home directory by using ~ character

. directory and .. directory

. and .. has special meaning in Linux. . (single dot) means the current directory and .. (double dot) means the parent directory. We can use these in various situations for daily activities.

$ cd ..

The above command changes the current directory to the parent directory.

ls command

We use ls command to list the files and directories inside any given directory. If you use ls command without any argument, then it will work on the current directory. We will see a few examples of the command below

$ ls
Applications	Library		Pictures	mongodb-data
Desktop		Movies		Postman
Documents	Music		Public
Downloads	OneDrive	mongodb
$ ls Documents/
Adobe
java-workspace
$ ls /
Applications	Volumes		etc		sbin
Library		bin		home		tmp
System		cores		opt		usr
Users		dev		private		var

In the last two commands, we provided a path as the argument to the ls command. / is a special directory, which represents the root directory in the Linux filesystem.

mkdir command

We can create new directories using mkdir command. For our example, we will create a code directory inside our home directory.

$ mkdir code
$ ls
code Desktop Documents Downloads

We can also create nested directories in a single command using the -p option.

$ mkdir -p dir1/dir2/dir3
$ ls dir1 dir1/dir2/
dir1/:
dir2

dir1/dir2/:
dir3

rm command

rm command is used to remove a file or directory. The -r option is being used to remove in a recursive way. With -f you force the removal, ignoring errors and never prompt. You can chain the flags, so instead of rm -r -f you can as well type rm -rf. But, always double-check before you use the rm -rf command, if you by mistake give this command in your home directory or any other important directory, it will not ask to confirm, but it will delete everything there. So, please be careful and read twice before pressing the enter key.

$ rm -rf dir1/dir2/dir3
$ls dir1/ dir1/dir2/
dir1/:
dir2

dir1/dir2/:

cp command

We use the cp command to copy a file in the Linux shell. To copy a folder with its contents recursively use the cp command with the -r flag. We use the cp file_to_copy new_location format. In the example below, we are copying the file1.txt to file2.txt.

$ cp file1.txt file2.txt
$ ls -l
-rw-rw-r--.    1.    fedora fedora    75 Jan 01 05:56 file2.txt
-rw-rw-r--.    1.    fedora fedora    75 Jan 01 05:59 file1.txt

In another example, I will copy the file flower.png from the Pictures directory in my home directory to the current directory.

$ cp ~/Documents/flower.png .

In the following example, I will be copying the images directory (and everything inside it) from the Downloads directory under the home to the /tmp/ directory.

$ cp -r ~/Downloads/images /tmp/

Renaming or moving a file

The mv command is used to rename or move a file or directory. In the following example, the file hello.txt is renamed to nothello.txt

$ mv file1.txt file2.txt
$ ls -l
-rw-rw-r--.    1.     fedora fedora.    75 Jan 01 03:23 file2.txt

tree command

tree command prints the directory structure in a nice visual tree design way.

$ tree
.
|- code
|- Desktop
|- Downloads
|- Music
|- Pictures

wc command

wc, short for word count, is a useful command which can help us to count newlines, words, and bytes of a file.

$ cat file1.txt
some text
$ wc -l file1.txt
1 file1.txt
$ wc -w file1.txt
2 file1.txt

The -l flag finds the number of lines in a file, -w counts the number of words in the file.

echo command

echo command echoes any given string to the display.

$ echo "Hello"
Hello

Redirecting the command output

In Linux shells, we can redirect the command output to a file, or as input to another command. The pipe operator | is the most common way to do so. Using this we can now count the number of directories in the root (/ ) directory very easily.

$ ls /
bin    boot    dev    etc    lib
$ ls / | wc -w
5

The | is known as a pipe. To know more about this, watch this video.

Using > to redirect output to a file

We can use > to redirect the output of one command to a file, if the file exists this will remove the old content and only keep the input. We can use >> to append to a file, which means it will keep all the old content, and it will add the new input to the end of the file.

$ ls / > file1.txt
$ cat file1.txt
bin
boot
dev
etc
lib
$ ls /usr/ > file1.txt
$ cat file1.txt
bin
games
include
lib
$ ls -l /tmp/ >> file1.txt
$ cat file1.txt
bin
games
include
lib
total 378
-rwxrwxr-x.    1    fedora fedora    45 Jan 01 05:34 test.java
-rw-------.    1    fedora fedora    45 Jan 01 06:55 somefile

That’s it for this article, I hope this article helps you to understand the most basic Linux commands as a newbie. If this article, helps you then please share this with your friends and colleagues.