Take the official answer!
Karma is a feature that shows the popularity of a member. Members, if allowed, can 'applaud' or 'smite' other members, which is how their popularity is calculated. You can change the number of posts needed to have a "karma", the time between smites or applauds, and if administrators have to wait this time as well.
Whether or not groups of members can smite others is controlled by a permission. If you have trouble getting this feature to work for everyone, double check your permissions.
My official answer xD
Karma is nonthing at all. Forget it. Just this. But try not to be decreased ;P
locked there are out there above 7-8 similar threads!