unix Permissions CHOWN
Example
To change own:group you use command chown user:group
e.g. chown owner:group or if owner and group are same you can use chown owner: (because linus assumes owner:group are same).
To change own:group you use command chown user:group
e.g. chown owner:group or if owner and group are same you can use chown owner: (because linus assumes owner:group are same).
