Toribash
Rank means how much qi you have within your belt category. If you have 1 QI, you'll have low rank, if you have 19 qi, you'll be high ranked within white belt. Likewise, a player with 4999 qi is rank 1 on 4th dan black, and when he gets 5000 qi, he's the lowest ranked 5th dan. QI means games played, if you win or lose doesn't make a difference. For future reference, threads like these go in the Beginner Sanctuary.
Actually win/loss does make a difference. Not in the way you would think though. If two players have 19 qi, then the one with the better win percentage (wins divide by qi) gets the better rank.
A certain recluse, I know not who, once said that no bonds attached him to this life, and the only thing he would regret leaving was the sky.