Linux
Find file by name
find /path -name "filename"
Find file by type
Find files modified in last 7 days
Search text in files
Search with case insensitive
Search with line numbers
Replace text in file
sed -i 's/old/new/g' file
Replace text in multiple files
find . -type f -exec sed -i 's/old/new/g' {} +
Extract column from file
Show disk usage
Show directory size
Show directory sizes recursively
Show memory usage
Show system info
Show running processes
Show process tree
Kill process by PID
Kill process by name
Kill process forcefully
Monitor processes
Show network connections
Show listening ports
Download file
Download with curl
Change file permissions
Change file owner
Change owner recursively
chown -R user:group /path
Show first 10 lines
Show last 10 lines
Follow file changes
Sort file
Remove duplicate lines
Count lines in file
Count words in file
Create tar archive
tar -czf archive.tar.gz /path
Create zip archive
Start service
systemctl start servicename
Stop service
systemctl stop servicename
Restart service
systemctl restart servicename
Enable service on boot
systemctl enable servicename
Check service status
systemctl status servicename
List services
systemctl list-units --type=service
Show environment variables
Set environment variable
Show command history
Search command history
Run command in background
Run command detached
Show current user
Switch user
Switch to root
Run command as root
Show open files by process
Show files opened by user
Monitor file system events
Copy file with progress
Sync directories
Show CPU info
Show block devices
Show mounted filesystems
Unmount filesystem
Show network interfaces
Show routing table
Test network connectivity
Show DNS lookup
Show DNS records
Show listening ports
lsof -i -P -n | grep LISTEN
Check port availability
Compress file
Decompress file
Compress with bzip2
Decompress bzip2
Show file type
Compare two files
Show file differences side by side
Monitor system resources
Show disk I/O
Show network traffic
Show process network usage
Archive and compress
tar -czf archive.tar.gz /path
tar -xzf archive.tar.gz path/to/file
List archive contents
Create symbolic link
Remove symbolic link
Change permissions recursively
Set sticky bit
Set SUID bit
Show file timestamps
Change file modification time
touch -t YYYYMMDDHHMM file
Monitor log file
tail -f /var/log/file.log
Search in log files
grep "error" /var/log/*.log
Show last log entries
Follow system logs
Show logs for service
journalctl -u servicename
Show logs since time
journalctl --since "1 hour ago"
Set system date
date -s "YYYY-MM-DD HH:MM:SS"
Show calendar
Show uptime
Show load average
Show kernel version
Show all users
Show groups
Add user
Delete user
Change user password