In blackjack, the player with aces (high cards) is presumed to have 21. If the player has a two or three, they are considered to have 17 and 18, respectively.
If the dealer has a two or three, they must first check against the player’s hand to see if they have 21. If the player has 21, then the dealer must give them a card that is higher than their hand (e.g. a four).
If the dealer does not have 21, they must give the player a card that is lower than their hand (e.g. a two). .
The goal of blackjack is to get as close to 21 without going over. This is done by counting cards and making decisions about whether to stay or hit.
In order to make this decision, the dealer will give you a number between 1 and 10 which tells you how many points you are worth.
If you are at or below this number, then you should hit. If you are above this number but not equal to it (i.e., there is another card between your current hand and 21), then you should stay put and draw another card.
If you are above 21 and equal to it (i.e., there is no other card between your current hand and 21), then you can either hit or stand depending on what other cards are currently in play.
So in short, in order for blackjack dealers to know whether or not the player has 21, they need to look at the player’s hand and see if they have an ace, two or three; if so, they will know how much money the player has and what their point value is currently.
