Master Essential Linux Commands: From Basics to Advanced Operations

Basic Commands

1. pwd

The pwd command displays the current working directory.

$ pwd
/home/user

2. ls

The ls command lists files and directories in the current location.

$ ls
Desktop Documents Downloads Music Pictures Public Videos

Use ls -l for a detailed list and ls -a to show hidden files.

3. cd

The cd command changes the current directory.

$ cd Documents
$ pwd
/home/user/Documents

Use cd .. to move up one level.

4. mkdir

The mkdir command creates a new directory.

$ mkdir myfolder

5. rm

The rm command removes files or directories.

$ rm myfile.txt
$ rm -r myfolder

6. cp

The cp command copies files or directories. $ cp myfile.txt myfolder/ Use the -r option to copy entire directories.

7. mv

The mv command moves or renames files and directories.

$ mv myfile.txt newfile.txt
$ mv myfolder/ ~/Documents/

Advanced Commands

1. grep

The grep command searches for a pattern within files and prints matching lines. $ grep "hello" myfile.txt Options: -i ignores case, -n shows line numbers.

2. ps

The ps command lists currently running processes.

$ ps
PID   TTY   TIME   CMD
1234  pts/0 00:00:01 bash
5678  pts/0 00:00:00 ps

Use ps aux for a detailed view of all processes.

3. top

The top command provides a real‑time view of system processes, CPU, and memory usage. $ top Press q to exit.

4. tar

The tar command creates and extracts archive files.

$ tar -cvf myfiles.tar myfile.txt myfolder/
$ tar -xvf myfiles.tar

Add the -z option to compress with gzip.

5. wget

The wget command downloads files from the web.

$ wget http://example.com/myfile.txt

6. curl

The curl command also downloads files and supports many protocols.

$ curl http://example.com/myfile.txt -o myfile.txt

Use -O to save with the remote filename, or -L to follow redirects.

7. ssh

The ssh command connects to a remote server to run commands.

$ ssh [email protected]
$ ssh [email protected] "ls -l"

Options: -p specifies a port, -i specifies an identity file.

8. scp

The scp command securely copies files between local and remote hosts.

$ scp myfile.txt [email protected]:/home/user/

Use -r to copy directories recursively and -P to set a custom port.