I see that you have asked about reputation. The board FAQ has it explained:
http://board.freeones.com/faq.php?faq=_#faq_cc
In short, it enables board members to rate each other's posts. It's kind of a virtual status marker and doesn't really matter, except that up until 2500 rep points you can also get MyFreeOnes (MyFO) points from gaining reputation. You've already gone waaaay beyond that limit and gotten all of the MyFO points to be gained from getting rep. :)
People usually give positive rep for good and useful posts. Negative rep on the other hand... Well, basically the only acceptable reasons for giving negative rep is when someone starts harassing other members, breaking rules or doing something else that disturbs the order of the board (and the real repercussions for those actions will be handed out by the moderators). It's not good form to give neg rep for plain disagreements. There is a system in place to track rep ***** as well.