Modify Permissions
If you are the owner of a file or directory you have the ability to alter a files permission settings.
The command used is:
chmod
You also have the option to add permissions(+), take away permissions(-) from any of three groups. User(u), group(g), other(o).
An example command looks as follows:
chmod go-rwx mysongs
This code is taking away the read, write and execute permissions from the person whom the file belongs and all others for the file called Mysongs.