This is how it's configured as standard, It can however be edited and the levels and title changed, I get the feeling that the forum's leves are still set at standard though.
The Green bars system is set differently.
Add one point for every 365 days since you joined the forum.
Add one point for every 1000 posts you have on the forum.
Add one point for every 1000 rep points you have already.
You require 125 posts or more and 50 reputation points for the reputation you give to count as positive or negative.
Again this is the standard settings.
You have to give reputation to 20 people to get back around to someone you’ve already given reputation to.
The green squares show you have positive reputation, while the red shows negative. Bright green and bright red mean higher values of positive or negative. The most you can get in either direction is 11 squares, 5 dim and 6 bright. You can get more and more reputation, you'll still stop at 11 squares.
There is also a grey square that you will see in your User Control Panel, where you can view recent reputation left for you by others. If you see a grey square that means that whoever left you rep, but they don't have enough power to give anything more than a big fat zero.
There is also a black square for disabled rep, but currently only mods/admin have the choice.