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SkillSnap Official GuideUpdated 7/24/2026
Linux Terminal
The backbone of the web. Master package managers, systemd services, and modern networking commands.
Package Managers (The Big 3)
Know the specific manager for your distribution.
Debian / Ubuntu / Mint
StandardUses 'apt'. Friendly and widely supported.
Requirement: Install: sudo apt install [app] | Update: sudo apt update
RHEL / Fedora / CentOS
StandardUses 'dnf'. Robust and enterprise-focused.
Requirement: Install: sudo dnf install [app] | Update: sudo dnf check-update
Arch / Manjaro
StandardUses 'pacman'. Fast, rolling-release focus.
Requirement: Install: sudo pacman -S [app] | Update: sudo pacman -Sy
Systemd (Service Management)
Start service immediatelysudo systemctl start [service]
Start service on bootsudo systemctl enable [service]
Check if running/deadsudo systemctl status [service]
View logs for specific servicejournalctl -u [service]
Follow logs in real-timejournalctl -f
Hardware Resources
List Block Devices (Drives/Partitions)lsblk
Show RAM/Swap in GB/MBfree -h
CPU Architecture Detailslscpu
List USB Deviceslsusb
Run command every 2s (Live Monitor)watch [cmd]
Modern Networking
Show IP address & Interfaces (replaces ifconfig)ip a
Show Routing Tableip r
Show listening ports & processes (replaces netstat)ss -tulpn
Permissions (chmod)
Make file executablechmod +x [file]
Safe Default (Owner full, others read/exec)chmod 755 [file]
Unsafe (Everyone has full access)chmod 777 [file]
Change Owner and Groupchown user:group [file]
Productivity Hacks
Re-run last command as sudosudo !!
Run command in background[cmd] &
Recursive text search in foldergrep -r 'text' [path]
Re-run last command starting with 'grep'!grep
Create shortcut (e.g. in .bashrc)alias [name]='[cmd]'
Emergency Tools
View last kernel messages (Hardware errors)dmesg | tail
Force kill app (Nuclear Option)killall -9 [app]
Interactive Process Manager (Better than top)htop
Text Editors
💡nano: Beginner friendly. Ctrl+O to save, Ctrl+X to exit.
💡vim: Powerful but complex. Emergency exit: Esc -> :q! -> Enter.