How do ranks even work?

Oct 26, 2018
I never played Halo 2 online when it was still on Xbox unfortunately. I also happened to miss when live servers were up with gfwl. So basically I never got to see ranks, clans or any match making. I just wanna know how the ranking system will be if you guys ever add it. My question is how do ranks work? Hopefully I can get an answer even though that question is pretty vague...