Strat, this question is a follow-up to
Unix controls.

Originally Posted by
andyhaus1057
How do octal access control codes work?
The Wikipedia article I referenced in
Unix controls covers this. What isn't clear?

Originally Posted by
andyhaus1057
How do you set access controls with command line options instead of octal codes?
See the
chmod command man page or the man page on your system, particularly the parts regarding specifying the parameters of the command using symbolic mode. Only root or the file's owner can make changes. Example:
chmod u=rwx MyFile.