In poker, the highest hands determine the winner in a showdown. The ranking starts with a Royal Flush, the ultimate hand consisting of A, K, Q, J, and 10 of the same suit. Next is a Straight Flush, five consecutive cards of the same suit. Four of a Kind follows, featuring four cards of the same rank. A Full House, combining three of a kind and a pair, ranks next. Other strong hands include Flush, Straight, Three of a Kind, Two Pair, and One Pair, with a High Card being the lowest. Mastering these rankings is essential for strategic play.