File security - File system rights management

1. ls -l
2. chmod
3. chmod octal
4. Change ownership with chown
5. Change group only using chgrp
6. Default file permissions: umask
7. Shell Script
8. Perl
9. Python
10. Exercise: Create Bash script
11. Exercise: File security
12. Exercise: Remove write protected file
13. Exercise: chmod
14. Solution: chmod