You'll be surprised to hear this - but yes they are rigged.

Why else would they give out up to 200% bonuses on your initial deposit if they weren't confident of profits? All casinos are based on some type of standardized casino game which always favors the house. This is commonly referred to as the "house edge". The rules of each casino vary to change this house edge.

For example in blackjack, some casinos allow the house to hit on a soft 17 or allow doubling on any hand. By varying these rules the house edge can be changed. Make sure you are familiar with the rules and the probability of the particular casino you are playing. Not all casinos are alike and the odds of some online casinos are seriously stacked against you.

Regarding the house cheating the player in more devious ways: I've seen casino software where the administrator can simply pre-select the amount they can win in all the games. This house edge can be instantaneously changed without the player knowing about it. In one instance, I've seen blackjack odds that are at an 85% payout rate! Due to confidentiality and personal health issues I am not about to reveal these casinos but I can tell you that most reputable casinos particularly those provided by top end software providers do not engage in these practices. At times I do admit the so called "random number generator" doesn't seem some random when you lose 90% of blackjack hands.

Refer to my section on how to identify dishonest casinos. If you do suspect a cheating casino see if they have a system where you can see archived game records.

Most casinos however make most of their profits from novice players who do not know how to play the games which further increases the house edge. Players splitting face cards and standing on soft 16 are a casino operator's bread and butter. I've played at Intercasino where other players (group tables) are splitting 4's with the dealer holding a 6 and to top it off betting 25% of their bank. The lack of knowledge of average players contributes to a bulk of a casino's earnings.