Blackjack is a simple game, you have to make 21 points, or a value closer to this number than the dealer. Two cards are dealt to both you and the dealer, and afterwards you have the option of requesting as much cards necessary to hit 21 or reach a closer value. If the first two cards satisfy you, you can stop.

However after the two cards have been dealt you can choose to play Double Down which means that the bet will be doubled and you will only be allowed to hit one more card. It is advisable to select Double Down only when you are very confident that you may win.

Be advised that the Double Down rule is not the same in all casinos, some will let you play this option only with the first two cards, others only when you have certain cards, others will let you double when you have hit a pair, and so on.

This option is available when playing blackjack in a land casino as well. You will have to place the cards faced up in front of the bet when you want to place this bet. Also you can place an additional bet near the original bet, not on top of it. You can place any amount you wish when you place the second bet but it is advisable to always place the maximum amount possible.