You can add or deduct karma of one person in every six hours. Most members do not bother about Karma. I've noticed that my karma is getting reduced by one every day. It appears that the member involved logs in daily and reduces my karma.
Karma is index of one's popularity. As most members are inactive in this regard, this is of no significance.
Karma is what is you give a thumbs up to a person, if you like the person and his knowledge shared in boddunan, we can also appreiciate him in that manner..