Here's the (totally awful) honor system of Vanilla:
(numbers are not exact but globally right, also percentage of player in each tier changed depending on patch)
(1) kill other faction player and win battleground to get honor points
(2) at the end of the week, there will be a ranking of the player in your faction based on who got the more honor points during that week
(3) the top 0.2% of the player will be in the first tier of reward and get 12'000 rank points (not to be confused with honor point) then the next tier (which is between 0.2 and 0.7%) will receive 11'000 rank points, then the next tier 10'000 rank points, etc
(5) to get to rank 14 you must get 60'000 rank points (rank 13 - 55'000, rank 12 - 50'000)
(6) each week you decay 20% of your current rank points
That's all!
practical exemple no1: Darklegolass666 is rank 5 because he has a total of 15'000 rank point at the beginning of the week. He plays like a madman all week and achieve to be the first of his faction (gg darklegolass666) he will earn 13'000 rank points! next week he will have 15'000 (total before) - 3'000 (decay) + 13'000 (total of the week) so: 25'000 rank point and reach rank 7!
practical exemple no2: Darklegolass666 is now rank 13 (55'000 rank points) however he can't play 4 days because he must go visit grandma. Darklegolass666 just manage to be in the first 20% of the player of the week and only win 6000 rank points. This could sound ok but because of decay, he will not only not get rank point but lose some! 55'000 - 11'000 + 6000 = 50'000! he's back at rank 12! suck to visit grandma!
tl;dr: system totally sucks and you have to organise all your faction top player to make rotations about who should be ranked in the first tier and never take a break once you're above rank10!