`gpasswd` - administer /etc/group

gpasswd [-a USER | -d USER] GROUP

Options you will use

-a USER: add USER to GROUP
-d USER: remove USER from GROUP (usermod cannot remove one group)

Examples

$ sudo gpasswd -d appuser ops

Removing user appuser from group ops

Taught in

4.3 Users, groups, and who you are right now

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