Linux & Terminal57 entries

Linux Commands

Essential Linux commands for file management, processes, networking, and system administration

1File & Directory Operations

`ls -la`	List all files with details
`cd <dir>`	Change directory
`pwd`	Print working directory
`mkdir -p <dir/sub>`	Create nested directories
`rm -rf <dir>`	Remove directory recursively (use with caution)
`cp -r <src> <dest>`	Copy directory recursively
`mv <src> <dest>`	Move or rename file/directory
`touch <file>`	Create empty file or update timestamp
`ln -s <target> <link>`	Create symbolic link
`find . -name "*.log"`	Find files by name pattern

`cat <file>`	Display file contents
`less <file>`	View file with pagination
`head -n 20 <file>`	Show first 20 lines
`tail -f <file>`	Follow file updates in real-time
`wc -l <file>`	Count lines in file
`sort <file>`	Sort file lines
`uniq`	Remove duplicate adjacent lines
`diff <file1> <file2>`	Compare two files

`chmod 755 <file>`	Set rwxr-xr-x permissions
`chmod +x <file>`	Make file executable
`chmod -R 644 <dir>`	Set permissions recursively
`chown user:group <file>`	Change file owner and group
`chown -R user:group <dir>`	Change ownership recursively
`umask 022`	Set default file creation permissions

`ps aux`	List all running processes
`ps aux \| grep <name>`	Find process by name
`top`	Real-time process monitor
`htop`	Interactive process viewer
`kill <PID>`	Send SIGTERM to process
`kill -9 <PID>`	Force kill a process
`killall <name>`	Kill all processes by name
`nohup <cmd> &`	Run command immune to hangups
`bg / fg`	Move job to background / foreground

Variables, loops, conditionals, functions, and scripting patterns for Bash shell

Vim modes, navigation, editing, search, and plugin essentials

SSH connections, key management, SCP/SFTP transfers, tunnels, and security hardening