The En Prison (In Prison) rule is applied by some land-based and online roulette on even bets only. When the ball lands on the zero, the house allows the player to take back half of his bet or he can leave it for another spin. However, if for the second time, the result is another zero, the whole bet goes to the house.

In the early days of online casinos, not all that many people wanted to give any of it a try. Players want their online Blackjack playing environment to be as exciting as it is at real life casinos. Therefore, gambling sites introducing live dealers is considered to be a good thing by most.