Below is an A to Z reference of essential Unix/Linux commands. This will serve as your quick-access arsenal whenever you need to execute system tasks, automate workflows, or dominate the terminal like a pro

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📜 Essential Linux Commands (A-Z)

🅰️ A Commands

• alias → Create shortcuts for commands
• awk → Powerful text-processing tool for data extraction and manipulation

🅱️ B Commands

• basename → Extract filename from a path
• bg → Resume a job in the background
• bzip2 → Compress files

🌊 C Commands

• cat → View file contents
• cal → Display a calendar
• cd → Change the working directory
• chmod → Change file permissions
• chown → Change file ownership
• cp → Copy files and directories
• curl → Transfer data using URLs
• cut → Extract specific columns from a file

🏗️ D Commands

• date → Display current date and time
• df → Show disk space usage
• du → Show directory size
• diff → Compare two files line by line
• dig → Query DNS records
• dmesg → Show system boot and kernel messages

📜 E Commands

• echo → Print text to the terminal
• exit → Close the terminal session
• env → Show environment variables
• exec → Replace the shell process with another process

🔍 F Commands

• file → Determine file type
• find → Search for files
• free → Show RAM usage
• fsck → Check and repair filesystem

🛠️ G Commands

• grep → Search for patterns in text
• git → Version control system
• groupadd → Create a new user group
• gzip → Compress files
• gawk → GNU version of awk

🏠 H Commands

• head → Display first 10 lines of a file
• hostname → Show or set the system hostname
• htop → Interactive process viewer
• history → Show previously run commands

📡 I Commands

• ifconfig → Show network interfaces (deprecated, use ip)
• ip → Configure network interfaces
• iptables → Configure firewall rules

⏳ J Commands

• jobs → List background jobs
• journalctl → View system logs

❌ K Commands

• kill → Terminate a process by PID
• killall → Kill processes by name
• kmod → Load or unload kernel modules

📂 L Commands

• ls → List directory contents
• ln → Create symbolic or hard links
• locate → Find files quickly using an index
• lsblk → List information about storage devices

📦 M Commands

• man → Show manual pages for commands
• mkdir → Create directories
• mv → Move or rename files
• mount → Mount a filesystem
• md5sum → Generate MD5 checksum for a file

🌐 N Commands

• nano → Simple text editor
• netstat → Show network connections (deprecated, use ss)
• nslookup → Query DNS records

🏗️ O Commands

• open → Open files (macOS)
• od → Display file contents in different formats

🚀 P Commands

• ping → Check network connectivity
• pwd → Show current working directory
• ps → Show running processes
• passwd → Change user password
• pkill → Kill processes by name

❓ Q Commands

• quit → Exit applications like vi or less
• quota → Display user disk usage

♻️ R Commands

• rm → Delete files
• rmdir → Remove empty directories
• reboot → Restart the system
• rsync → Synchronize files between systems

🔐 S Commands

• ssh → Secure shell for remote access
• sed → Stream editor for modifying text
• shred -> Overwrite a file to hide its content, and optionally delete it
• sort → Sort lines of a file
• sudo → Run a command as superuser
• systemctl → Manage system services
• scp → Securely copy files over SSH

📌 T Commands

• tail → Show last 10 lines of a file
• tar → Archive files
• touch → Create an empty file
• top → Show running processes in real-time
• traceroute → Trace the path to a network host

🔧 U Commands

• uptime → Show system uptime
• uname → Show system info
• unzip → Extract ZIP archives
• useradd → Create a new user

📖 V Commands

• vi → Command-line text editor
• vim → Improved version of vi
• vmstat → Show system performance stats

🌍 W Commands

• wget → Download files from the web
• who → Show logged-in users
• watch → Re-run a command at intervals

❌ X Commands

• xargs → Pass input from one command to another

🔍 Z Commands

• zip → Create compressed ZIP archives
• zcat → View contents of a compressed file