Many online casino players don't really understand the concept of a house edge. The house edge is, very simply, a percentage of the bets placed that the casino expects to keep for itself. These numbers are calculated to make sure that physical and online casinos are able to stay in business. Generally the house edge for casinos tends to fall a little bit below 6%. It's safe to say that for most games at most casinos, the higher the risk, the greater the reward is. Many of the casino players you see in the paper or hear about on the radio, which have been made millionaires from casinos, have done so by playing games where the odds were stacked against them.
It's important to remember when considering casinos, that at the end of the day, they are businesses. This is the explanation you'll get from most casino operators when questioned about the house edge. The house edge, also called casino advantage, is essentially the average money lost to the player's initial bet placed. It's the difference between what should be paid to you ideally (the true odds), and what the casino gives you. For games like blackjack or video poker, there isn't a built in profit, the house edge is zero. For other games, there is a built in profit.
Roulette is the perfect game to use as an example when explaining the house edge. Roulette games have thirty seven numbers on single zero tables, which is European roulette. American roulette has thirty eight numbers on a double zero table. If you simply calculate the odds, they would be 1 in 37 for the case of European roulette, and 1 in 38 for American Roulette. But the casino doesn't pay those odds if you win, it will only pay out 25 to 1 on both of the games. Therefore, the casino advantage is 5.26% with American roulette and 2.7% with European roulette. The system works very similarly with craps dice as there are twelve numbers on a pair of dice, and there are different payout odds.
When it comes to playing blackjack, the house edge works in an entirely different manner, as the odds are changing constantly. If a card is randomly dealt, the odds of the player or the house getting the advantage go back and forth all the time. Every time a card is dealt, the cards that remain provide new odds. This is the reason that card counters in blackjack are able to win so much money. The same goes for video poker.
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