CLI Cheat Sheet

Basic Commands

Command	Description	Examples/Options
`pwd`	Print current working directory.
`ls`	List files in the directory.	`ls -l`, `ls -a`, `ls -lh`
`cd [dir]`	Change directory.	`cd ..`, `cd ~`
`mkdir [dir]`	Create a new directory.
`rmdir [dir]`	Remove an empty directory.
`cp [src] [dest]`	Copy files or directories.	`cp -r [src] [dest]` (recursive)
`mv [src] [dest]`	Move/rename files or directories.
`rm [file]`	Remove a file.	`rm -r [dir]` (recursive), `rm -f [file]` (force remove)

File Viewing and Editing

command	description	examples/options
`cat [file]`	Print file content to stdout.
`less [file]`	View file content with pagination.
`head [file]`	Display the first 10 lines of a file.
`tail [file]`	Display the last 10 lines of a file.	`tail -f [file]` (follow changes)
`nano [file]`	Open a file in the nano text editor.
`vi [file]`	Open a file in the vi text editor.	Requires Vi is installed

File Permissions

Command	Description	Examples/Options
`chmod [permissions]`	Change file permissions.	`chmod 755 [file]`
`chown [user]:[group]`	Change ownership of a file.

Searching and Finding Files

command	description	examples/options
`find [dir] -name [pattern]`	Find files in a directory hierarchy.
`grep [pattern] [file]`	Search for a pattern in a file.	`grep -r [pattern] [dir]`, `grep -i [pattern] [file]`

Compression and Archiving

command	description	examples/options
`tar -cvf [archive.tar]`	Create a tar archive.
`tar -xvf [archive.tar]`	Extract a tar archive.
`gzip [file]`	Compress a file with gzip.
`gunzip [file.gz]`	Decompress a gzip file.

Networking

command	description	examples/options
`ping [host]`	Send ICMP echo requests to a host.
`ifconfig`	Display network interfaces (Use `ip a` on newer systems).
`curl [url]`	Download content from a URL.
`wget [url]`	Download files from a URL.

Process Management

command	description	examples/options
`ps`	Display running processes.	`ps aux` (detailed view)
`top`	Real-time view of system processes.
`kill [pid]`	Terminate a process by its PID.	`kill -9 [pid]` (force kill)
`htop`	Enhanced top with interactive process monitoring.

System Information

command	description	examples/options
`df -h`	Display disk space usage in human-readable format.
`du -sh [dir]`	Display size of a directory.
`free -h`	Show available and used memory.
`uname -a`	Display detailed system information.
`uptime`	Show system uptime.

Package Management (for Debian/Ubuntu)

command	description	examples/options
`sudo apt update`	Update the package list (Ubuntu/Debian).
`sudo apt upgrade`	Upgrade installed packages (Ubuntu/Debian).
`sudo apt install [pkg]`	Install a package (Ubuntu/Debian).
`sudo apt remove [pkg]`	Remove a package (Ubuntu/Debian).

File Redirection and Piping

command	description	examples/options
`>`	Redirect output to a file (overwrites).
`>>`	Redirect output to a file (appends).
`<`	Redirect input from a file.
`\|`	Pipe output of one command into another.	`cat file.txt \| grep 'text'`

Environment Variables

command	description	examples/options
`echo $VARIABLE`	Display the value of a variable.
`export VAR=value`	Set or modify an environment variable.
`env`	Display all environment variables.

Command History

command	description	examples/options
`history`	Show command history.
`!!`	Repeat the last command.
`!n`	Run the command numbered `n` in history.

Shortcuts

command	description	examples/options
`Ctrl + r`	Search through command history interactively.
`Ctrl + c`	Stop a running command.
`Ctrl + z`	Suspend a running command.
`Ctrl + d`	Exit the terminal.
`Ctrl + a`	Move to the beginning of the line.
`Ctrl + e`	Move to the end of the line.
`Ctrl + u`	Clear the line before the cursor.
`Ctrl + k`	Clear the line after the cursor.
`Ctrl + l`	Clear the terminal screen.