In blackjack, tie-breaking rules come into play when both the player and the dealer have hands that total the same value. In such cases, the most common outcome is a push, meaning the player's bet is returned, and no money is won or lost. This typically happens when the player and dealer both have the same hand value, such as both showing 18. However, if the dealer has a blackjack (an Ace and a 10-point card) and the player does not, the dealer wins outright, and the player loses their bet.