There are three major variations: American, European, and French. European roulette is the baseline style for determining odds with 36 positive numbers split between black and red, plus a 0. American roulette has the toughest odds because it includes pockets for both 0 and 00, so there’s a 1-in-19 chance that the spin ends up voiding your bet. French roulette online is the most generous version with a built-in payout to cut your losses: if the ball lands on 0, you get 50% of your bet back.