Basic Linux commands

In Linux system all basic and advanced tasks could be done by using commands. Linux commands help you to interact with the system.  We have to run the commands on terminal, in Window OS it is called as command prompt. By using terminal, we can interact with the Linux system.

1.      ls – list

This command is used to display or used to list the contents of a directory.

2.      ls -ltr

       This command is used to list the files according to which time they were created.

       Here, l-long listing, t-time, r-reverse order.

3.      pwd – present working directory

It will show you the present working directory. 

4.      cd – change directory

It is used to change the directory.

Syntax:

cd <directory_name>     

e.g.,

               cd Desktop

5.      mkdir – make directory

By using this command, we can create a directory.

Syntax:

mkdir <directory_name>

e.g.,

               mkdir user

6.       rmdir – remove directory

This command is used to remove or delete empty directory. But if the directory we are going to delete contains files or subdirectories, such directory can’t be removed by this command.

Syntax:

rmdir <directory_name>              

e.g.,

               rmdir user

This will delete the directory ‘user’ if it is empty otherwise it will give an error.

7.      rm – remove

This command removes files, directories.

Syntax:

rm <directory_name>

e.g.,

removing one file –

               rm file1.txt

removing more than one files at a same time

               rm file1.txt file2.txt

8.      cp- copy

This command is used to copy one file into another file or copy a file to specified path

Syntax:

cp <source_file_name> <destination_file_name>

cp <file_name> <path, where you want to copy this file> 

        e.g., 

                  cp a.txt b.txt

                  cp a.txt /Desktop  

9. mv – move

This command is used to move directory or a file from one location to another.

Syntax:

mv <file_name> <directory_path>

e.g.,

               mv a.txt Directory

10.  tail –

This command is used to display the last 10 lines of a file.

Syntax:

tail <file_name>

11.  su – super user

      This command is used to provide the administrative access to the other user. When you enter this command, it will ask you for a password at that time you have to provide the password for that user.

Syntax:

su  <user_name> 

12.  sudo -super user do

this command especially used as a prefix with some other commands to run with some extra privileges. The working of this command is same as ‘Run as Administrator’ option in Windows.

Syntax:

sudo command

13.  clear-

This command clears the terminal screen.

Syntax:

Clear 

14.  exit –

This command is used to exit from the currently working shell.

Syntax:

exit

15.  wc – word count

This command is used to count the characters, words, lines in a specified file.

Syntax:

wc <file_name>