I added Everyone to permissions. So can I safely remove Administrators, Authenticated Users, System, Users?

[scherz0]

I'm assuming that "Everyone" includes "Administrators, Authenticated Users, System, Users". Please see screenshot below. After I added everyone, are all these four other groups redundant? Can I harmlessly remove all these four other groups from the list?

 

[DVDR_Dog]

Not necessarily. See that advanced tab? You many wish to individually assign those to specific users or groups. In the mean time, no harm, no foul. You can leave things alone with no negative consequences.