If you mean reputation points, what've seen is it goes up if you post regularly and in a short time, thus is you post everyday your reputation power goes up. Frecuent posters. I could have registered a year ago and have only 20 posts and have 1 of reputation power but if someone registered a week ago and has 20 post probably has around 5 of reputation power.
Now regular posts are first checked to see if they are quality posts and not simple answers that are only fillers. Those posts dont count and sometimes they dont even appear. So basically, try to use your head when answering that way people get better answers and the forum stays knowlegable.
If you ask me this is the first time I see this system on a forum, but for now it has worked and we have very little "hacks" I cant imagine what this forum will be in the near future.
It's not really clear, even the admin isn't too sure how it all works but here is my best guess.
You recieve + or - Rep when another member credits your post. The degree of how much you gain or lose is controlled by the issuers Rep Power. (For example if a n00b or alias account +reps your post it will probably rise by 1 point but if an admin credits your post then likely it will rise by alot more.)
Your Rep points (viewable via the User CP) contributes to how many 'gems' you have to your name.
These increase after a certain rep point milestone (quantity). Rep points also add to your own Rep Power but, this is also calculated by other factors such as length of membership and frequency of activity (posts per day) and others.
In general someone who posts decent quality posts regularly will quickly become popular and 'reputable' among the forums.
If you want to aquire rep as a bragging right to authority then just be nice and don't post some BS comments. From what I've seen, posting links in the PSN Store Links thread seems to be a good way to earn +Rep as Aldostools is doing quite fine in his Rep in such a short time.
Hope this clears things up for alot of people out there. Happy posting!
Go earn those Rep Points!!