File Search Commands:
1. find directory -name “filename“ – Search for files by name
2. find directory -type f -name “*.txt” – Find specific type of files
3. grep “text” filename – Search for text in a file
4. grep -r “text” directory – Recursively search for text in a directory
5. locate filename – Quickly find a file
6. which command_name – Show the full path of a command
7. whereis command_name – Show the binary, source, and manual location of a command
Permission Management Commands:
8. chmod 755 filename – Change file permissions
9. chmod +x filename – Add executable permission
10. chown user:group filename – Change file owner
11. chgrp group_name filename – Change file group ownership
12. umask – Show or set the default file permission mask
System Information Commands:
13. uname -a – Show system information
14. hostname – Show hostname
15. uptime – Show system uptime
16. whoami – Show current username
17. who – Show logged-in users
18. w – Show logged-in users and their activities
19. date – Show or set system date and time
20. cal – Show calendar
21. free -h – Show memory usage
22. df -h – Show disk space usage
23. du -sh directory – Show directory size
24. top – Dynamically display process information
25. htop – Enhanced version of top (requires installation)
26. ps aux – Show all processes
27. ps -ef | grep process_name – Find a specific process
28. kill PID – Terminate a process
29. kill -9 PID – Forcefully terminate a process
30. lscpu – Show CPU information
31. lsblk – List block device information
32. lspci – List PCI devices
33. lsusb – List USB devices