Blackjack, also known as twenty-one or Pontoon, is one of the most popular casino card games in the world. Much of blackjack's popularity is due to the mix of chance with elements of skill, and the publicity that surrounds card counting.

Blackjack, unlike other games, has an element of player choice, players can actually reduce the casino advantage to a small percentage by playing what is known as basic strategy. This strategy determines when to hit and when to stand, and also determines when doubling down or splitting is the correct action.

The following rules are detrimental to the player

Less than 3:2 payout on blackjacks.

Player losing ties. This is just as bad as having a low blackjack pay out, since a tie will occur almost 8% of the time. A player will lose money up to and over twenty times faster at this game

The following rules are beneficial to the player:

Doubles are permitted on any two-card hand except a blackjack. This allows the player to choose to double when he is most likely to win, and not double when he is not likely to win.

Doubles are permitted after splitting. This allows a player to potentially get many bets out in a situation that he is likely to win, such as against a dealer card of 6, the worst card the dealer can have.

Early surrender; the ability to forfeit half your wager against a face or ace before the dealer checks for blackjack. This is beneficial because some hands a player has are so unlikely to win that its better to just surrender half the bet.

Normal (aka "late") surrender.

Re splitting Aces. Obviously this avoids a player getting a miserable total of 12.

Drawing more than one card against a split Ace. This allows a player to draw a weak soft total if the dealers is showing a high card.

Five or more cards with the total still no more than 21 as an automatic win (a "charlie "). This is not a commonly seen rule. Source: wikipedia