๐ง Linux Command Cheat Sheet: Essential Commands with Examples
Linux is a versatile and powerful operating system. The command line is your gateway to mastery. Here's your cheat sheet, packed with must-know commands and real-world examples, sprinkled with emojis to make learning fun! ๐
1. ๐ File and Directory Management
๐ List Files
ls
- List all files in a directory.
Example:
ls -la
-l
: Detailed listing-a
: Include hidden files
๐ช Change Directory
cd <directory>
Example:
cd /home/user/Documents
- Move to the "Documents" directory.
๐ Create a Directory
mkdir <directory_name>
Example:
mkdir my_project
๐๏ธ Remove a File or Directory
To remove a file:
rm <file>
Example:
rm example.txt
To remove a directory:
rm -r <directory>
Example:
rm -r old_directory
๐ Copy Files
cp <source> <destination>
Example:
cp file.txt /home/user/backup/
โ๏ธ Move or Rename Files
mv <source> <destination>
Example:
mv old_name.txt new_name.txt
2. ๐ File Viewing and Editing
๐ View File Contents
cat <file>
Example:
cat /etc/passwd
๐ Page Through File
less <file>
Example:
less largefile.log
โ๏ธ Edit Files
nano <file>
Example:
nano notes.txt
- Open the "notes.txt" file for editing in Nano.
3. ๐ฅ User Management
๐ Switch Users
su <username>
Example:
su root
๐ค Add a New User
sudo useradd -m <username>
Example:
sudo useradd -m alice
Set a password for the user:
sudo passwd alice
๐๏ธ Delete a User
sudo userdel <username>
Example:
sudo userdel alice
4. ๐ Permissions
๐ ๏ธ Change File Permissions
chmod <mode> <file>
Example:
chmod 755 script.sh
755
: Owner can read/write/execute; others can read/execute.
๐ Change File Ownership
sudo chown <user>:<group> <file>
Example:
sudo chown alice:users file.txt
5. ๐ Networking
๐ Check IP Address
ip addr
๐ก Ping a Host
ping <hostname_or_ip>
Example:
ping google.com
โฌ๏ธ Download a File
wget <url>
Example:
wget https://example.com/file.tar.gz
6. ๐พ Disk and System
๐ฟ Check Disk Space
df -h
๐ View Disk Usage
du -sh <directory>
Example:
du -sh /var/log
๐ Monitor System Processes
top
- Real-time view of system processes.
๐ง Check Memory Usage
free -h
๐ Reboot or Shutdown
Reboot:
sudo reboot
Shutdown:
sudo shutdown now
7. ๐ฆ Package Management
๐ฅ Install a Package (Debian/Ubuntu)
sudo apt install <package>
Example:
sudo apt install curl
๐งน Remove a Package
sudo apt remove <package>
Example:
sudo apt remove apache2
๐ Update System
On Debian/Ubuntu:
sudo apt update && sudo apt upgrade
8. ๐ Searching and Grep
๐ Find Files
find <directory> -name "<file_name>"
Example:
find / -name "*.log"
๐ Search Text in Files
grep "<text>" <file>
Example:
grep "error" /var/log/syslog
9. ๐ฆ Archiving and Compression
๐ฆ Create a Tar Archive
tar -cvf archive.tar <directory>
๐ Extract a Tar Archive
tar -xvf archive.tar
๐จ Compress Files
gzip <file>
Example:
gzip logs.txt
10. โก Miscellaneous
๐ Print Working Directory
pwd
โฑ๏ธ Check System Uptime
uptime
๐งน Clear Terminal Screen
clear
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