The main objective in Blackjack is to beat the dealer's hand without going over 21 points. Players aim to get as close to 21 as possible, either by having a higher hand value than the dealer or by the dealer busting. Winning can be achieved through getting a Blackjack, having a higher final hand than the dealer, or the dealer busting while the player's hand is still valid. The game involves strategic decisions about when to hit, stand, double down, or split, balancing the pursuit of a higher hand value against the risk of busting.