Showdown
The moment after the final betting round when remaining players reveal their hands to decide the winner.
At showdown the last player to bet or raise on the river shows first. If the river was checked through, the player closest to the left of the button shows first. A player who knows they are beaten may "muck" (discard face down) without showing.
The best five-card hand by the official hand rankings wins. If hands are equal the pot is a split pot.
Example
Player A shows AQ, player B shows AJ on A9742. Both have a pair of Aces, but A wins with the Queen kicker.