In poker, the strength of a hand determines the outcome of the game, making it essential for players to understand the hierarchy of hands. The best poker hands, ranked from highest to lowest, include the Royal Flush, Straight Flush, Four of a Kind, Full House, Flush, Straight, Three of a Kind, Two Pair, One Pair, and High Card. A Royal Flush, consisting of the Ace, King, Queen, Jack, and Ten of the same suit, is the ultimate hand, while a High Card hand signifies the weakest combination. Mastering these rankings is crucial for strategic gameplay.