LWM-Linux/01 - Introduction to Linux/Basic Linux Commands.md

# Basic Linux Commands

## 1. Navigation and File Management:

### a) pwd (Print Working Directory)
   - Shows the current directory path
   - Usage: pwd

### b) ls (List)
   - Lists files and directories in the current directory
   - Common options:
     -l: Long format with details
     -a: Show hidden files
     -h: Human-readable file sizes
   - Usage: ls [options] [directory]

### c) cd (Change Directory)
   - Changes the current directory
   - Usage: 
     cd [directory]
     cd .. (move up one directory)
     cd ~ (go to home directory)

### d) mkdir (Make Directory)
   - Creates a new directory
   - Usage: mkdir [directory_name]

### e) rmdir (Remove Directory)
   - Removes an empty directory
   - Usage: rmdir [directory_name]

### f) touch
   - Creates an empty file or updates timestamps
   - Usage: touch [filename]

### g) cp (Copy)
   - Copies files or directories
   - Usage: cp [source] [destination]
   - Options:
     -r: Recursive (for directories)

### h) mv (Move)
   - Moves or renames files and directories
   - Usage: mv [source] [destination]

### i) rm (Remove)
   - Deletes files or directories
   - Usage: rm [options] [file/directory]
   - Options:
     -r: Recursive (for directories)
     -f: Force deletion without prompting

## 2. File Viewing and Editing:

### a) cat (Concatenate)
   - Displays file contents
   - Usage: cat [filename]

### b) less
   - Views file contents page by page
   - Usage: less [filename]

### c) head
   - Displays the first few lines of a file
   - Usage: head [options] [filename]
   - Options:
     -n [number]: Specify number of lines

### d) tail
   - Displays the last few lines of a file
   - Usage: tail [options] [filename]
   - Options:
     -n [number]: Specify number of lines
     -f: Follow file updates in real-time

### e) nano
   - Simple text editor
   - Usage: nano [filename]

## 3. File Permissions and Ownership:

### a) chmod (Change Mode)
   - Modifies file permissions
   - Usage: chmod [options] [mode] [file/directory]
   - Example: chmod 755 file.txt

### b) chown (Change Owner)
   - Changes file ownership
   - Usage: chown [user]:[group] [file/directory]

## 4. System Information:

### a) uname
   - Displays system information
   - Usage: uname [options]
   - Options:
     -a: All information

### b) df (Disk Free)
   - Shows disk space usage
   - Usage: df [options]
   - Options:
     -h: Human-readable sizes

### c) du (Disk Usage)
   - Estimates file and directory space usage
   - Usage: du [options] [directory]
   - Options:
     -h: Human-readable sizes
     -s: Summary for directory

## 5. Process Management:

### a) ps (Process Status)
   - Lists running processes
   - Usage: ps [options]
   - Common options:
     aux: Detailed information for all processes

### b) top
   - Displays real-time system process information
   - Usage: top

### c) kill
   - Terminates processes
   - Usage: kill [options] [PID]
   - Options:
     -9: Force kill

## 6. Network Commands:

### a) ping
   - Tests network connectivity
   - Usage: ping [options] [destination]

### b) ifconfig
   - Displays network interface information
   - Usage: ifconfig

### c) ssh (Secure Shell)
   - Connects to remote systems securely
   - Usage: ssh [user]@[host]

## 7. Package Management (for Debian-based systems):

### a) apt-get update
   - Updates package lists
   - Usage: sudo apt-get update

### b) apt-get upgrade
   - Upgrades installed packages
   - Usage: sudo apt-get upgrade

### c) apt-get install
   - Installs new packages
   - Usage: sudo apt-get install [package_name]

## 8. File Compression:

### a) tar
   - Archives files
   - Usage: tar [options] [archive_name] [files/directories]
   - Common options:
     -c: Create archive
     -x: Extract archive
     -v: Verbose
     -f: Specify archive file
   - Example: tar -cvf archive.tar files/

### b) gzip
   - Compresses files
   - Usage: gzip [filename]

### c) gunzip
   - Decompresses gzip files
   - Usage: gunzip [filename.gz]

- [(1) The beginner’s guide to using terminal on Linux Mint - FOSS Linux.](https://www.fosslinux.com/103546/the-beginners-guide-to-using-terminal-on-linux-mint.htm.)
- [(2) Official User Guide - Linux Mint.](https://www.linuxmint.com/documentation/user-guide/Cinnamon/english_18.0.pdf.)
- [(3) BEGINNER'S GUIDE FOR LINUX - Start Learning Linux in Minutes - Tecmint.](https://www.tecmint.com/free-online-linux-learning-guide-for-beginners/.)
- [(4) Useful Basic Terminal Commands On Linux Mint 11 - HowtoForge.](https://www.howtoforge.com/useful-basic-terminal-commands-on-linux-mint-11.)