Essential Linux Commands for Efficient File and System Management

File and Directory Commands:

1. ls (List): Used to list files and directories in the current directory.

Example: ls will display a list of files and directories in your current location.

2. cd (Change Directory): Used to navigate between directories.

Example: cd /home/user/documents will change your current directory to "documents."

3. pwd (Print Working Directory): Displays the current working directory.

Example: pwd will show the full path of your current directory.

4. mkdir (Make Directory): Creates a new directory.

Example: mkdir new_folder will create a directory named "new_folder."

5. rmdir (Remove Directory): Deletes an empty directory.

Example: rmdir old_folder will remove the empty directory "old_folder."

File Manipulation Commands:

6. touch: Creates a new empty file.

Example: touch new_file.txt will create an empty file named "new_file.txt."

7. rm (Remove): Deletes files and directories.

Example: rm old_file.txt will delete the file "old_file.txt."

8. cp (Copy): Copies files and directories.

Example: cp source_file.txt destination/ will copy "source_file.txt" to the "destination" directory.

9. mv (Move): Moves or renames files and directories.

Example: mv file.txt new_location/ will move "file.txt" to the "new_location" directory.

File Content Viewing Commands:

10. cat (Concatenate): Displays the content of a file.

Example: cat file.txt will display the content of "file.txt."

11. more and less: View file contents one page at a time. Useful for long files.

Example: less long_file.txt will allow you to view "long_file.txt" one page at a time.

Text Search and File Search Commands:

12. grep (Global Regular Expression Print): Searches for text patterns in files.

Example: grep "keyword" file.txt will search for the word "keyword" in "file.txt."

13. find: Searches for files and directories.

Example: find /home/user -name "*.txt" will search for all files with a ".txt" extension in the "/home/user" directory.

File Permission and Ownership Commands:

14. chmod (Change Mode): Changes file permissions.

Example: chmod 644 file.txt will set read and write permissions for the owner and read-only permissions for others on "file.txt."

15. chown (Change Owner): Changes file ownership.

Example: chown user:group file.txt will change the owner and group of "file.txt" to "user" and "group."

Process Management Commands:

16. ps (Process Status): Lists running processes.

Example: ps aux will display a list of all running processes.

17. kill: Terminates processes.

Example: kill -9 process_id will forcefully terminate a process with the specified ID.

File Compression and Archiving Commands:

18. tar: Used to archive and compress files and directories.

Example: tar -cvzf archive.tar.gz folder/ will create a compressed archive of the "folder."

Disk Space Usage Commands:

19. df (Disk Free): Displays disk space usage.

Example: df -h will show disk space usage in a human-readable format.

20. du (Disk Usage): Shows the sizes of directories and files.

Example: du -sh directory/ will display the total size of the "directory" in a human-readable format.