When You start the game your rating will be at 1000 it will go up or down depends on how u play. The highest rating you can get is 1999 and the lowest rank is 1. Each day the best 3 games you play will be averaged and will give you your rating. Depends on how high your rating is you will get put into a division and will be put up with other players that are similar skill to you. You will only be rated if you play 3 games per day. I found this somewhere and i think you guys will like to see it to get a raw rating Bungie gets your kills + assists - deaths /3 - betrayals. It will get 3 deaths to negate a kill. Dont try to hard to win because if you dont win your rating will only go down by .96. Here's a good tip The more you play the better chance of getting 3 really good games in everyday. This is some good info that i found. Hope you guys that dont understand the rating system hope fully this helps you.