The plain and simple truth about online gambling odds is that the odds are always against you. Without exception, the odds always favor the house. This does not mean that you can't win, however, you just have to be smart and learn how to play the game right in order to improve your chances of winning.
Online casino games are virtual versions of the real thing and use random number generators to ensure the randomness of their results, much as any draw from the deck or spin of the wheel in real gambling is completely random. Casino games are referred to as independent trial processes in statistics. What this means is that the result of the last spin on a Roulette wheel, for example, has no impact on the results of the following spin. The three that came up on the last spin has absolutely no impact on the next spin. This is why statistically based gambling systems do not work.
Calculating Online Casino Odds
Online gamblers should also note that some games by nature have better odds than others. Keno and Let It Ride have some of the worst odds in the casino, while Roulette has some of the best. The even money bets in Roulette, red/black, odd/even, high/low, have almost a 50/50 chance. Only the presence of the green zero and double zero spaces make the odds slightly less than 50/50.
The example I just gave was based on an American Roulette wheel. American wheels have two green zero spaces. European wheels, on the other hand, have only a single zero space and thus the odds on European wheels are fractionally better than on American wheels. Black Jack has good player odds as well and is a good game to play for long periods.