For all variants of roulette, European roulette, the American Roulette or French roulette, the basic idea is to spin the wheel, allow the ball to land on a number, if the number is what you bet on, you get paid.
There are different types of roulette bets you can make. Each type of bet covers a set of numbers. After making your bet in the table layout, you click the spin button. The wheel rotates and the ball on the wheel lands up in to one of the pockets. If you have by chance covered the number on which the ball has landed in one of your bets, you get the payout accordingly.
Why the same number gives different players different payouts?
High-risk bets have fewer odds for winning per statistics give you more payout. Low risk bets that have more chances for winning, give you comparatively lesser payout.
It is wiser to play mix different types of bets covering maximum numbers in roulette to enjoy maximum opportunities to win. However, in the process you have to be sure that you are not betting more than what you win! You can easily bet on all the number in the table layout and be sure the one number is in your list, but will it be profitable is the challenge all about.
Understand the difference between single zero and double zero wheels. Know the better odds and challenge the risk. You will be playing 1:37 odds in French and European versions and 1:38 in the American roulette.
It is said that one roulette variant is better than the other is; however, both wheels are on chance. The versions with lesser odds to come with special rules like the En prison! The choice of the variant is a matter of attitude and risk appetite.