Hey,

Can someone explain to me the difference between:

# Members of the admin group may gain root privileges
%admin ALL=(ALL) ALL

# Allow members of group sudo to execute any command
%sudo   ALL=(ALL:ALL) ALL

If you are part of the admin group you can still use the sudo command (if so why have the sudo group)?
Isn't the sudo group redundant?

Thanks

Yes, it is redundant. Both groups are there for historical reasons, because removing any one of them could cause massive headaches to unsuspecting sysadmins. (I think "admin" is the old custom and "sudo" is the new standard, but I might have got it mixed up.)

Anyway, it is safe to delete the group that you don't use.