Four of a kind
Definition of four of a kind
A four of a kind is also called a "quad" in English. In French, it is called a square. A square is a hand that is characterized by having 4 cards of the same denomination. If you have JJ on JJAAT, you have a four of a kind. This hand is extremely strong. It beats a full hand, but loses to a straight flush. If you have a pair in your hand, you will hit a four of a kind to flop 0.24% of the time so yes, when that happens, it's quite an event!
Four of a kind and badbeat jackpot
If your poker room offers an badbeat jackpot, chances are that the minimum hand to qualify is a four of a kind. It can be a 2-of-a-Kind hand, sometimes an 8-of-a-Kind or a Jacks hand, depending on the room. The badbeat jackpot is a progressive jackpot that is hit when a player loses a hand with a four of a kind or better using both cards in hand. If the minimum qualifying hand is a 4-of-a-Kind 8, you will have to lose with a 4-of-a-Kind 8 to hit 50% of the progressive jackpot. The player who wins the hand will receive 25% of the progressive jackpot and the other 25% will be distributed equally among the players present at the table for that hand (you must have received 2 cards before the flop).