A bet in blackjack is a wager made by the player before the hand begins. The bet can be placed on any number between one and 21, with most bets placed around five or six.
A player must either stand (put up) or double (put money back on the table, plus another sum of money) if they are betting on a number that is already present on the table. If the number being betted on is not already present, a player can either stand or hit (play the hand without making a bet). .
The house edge in blackjack is about 0.5% for basic rules play, meaning for every 100 hands played, the house will make back about $5.
This house edge increases slightly through various play options such as doubling down and splitting cards.