Confusion with Online ratings

[TrueDestiny619]

I'm confused with how you are ranked online, it's not as annoying as BLOPS 2 zombie ranking system but is the higher rank you are the better and how do you gain more points as I sometimes get less points than others for finishing in 1st place. I'm not totally oblivious to this concept just curious as you start on 1000 which you don't see often in games