500, Five Hundred, is a game devised in America shortly before 1900 and promoted by the United States Playing Card Company, who copyrighted and marketed the rules in 1904. The game can be played by two to six players but the most common form is for four players in partnerships although some sources say that the game is primarily for three players. The game is an extension of Euchre which also incorporates the basic principles of Bridge.

500 has always been considered as a social card game and was highly popular in the United States until about 1920 when Auction bridge surpassed it. Subsequently, Contract Bridge drove it out of favour in America, but it continues to enjoy popularity in Australia. It is popular in New Zealand as well, and widely played in Quebec.

The game is played with a regular deck of cards with certain cards removed. Specialised "500" packs contain 63 cards, extended from 52 by the addition of a Joker, Elevens and Twelves in each suit, and two Thirteens in the red suits. The full pack is only required for six players, however, and is stripped of various cards for varying number of players, the basic principle that there should be just enough for ten cards per player and three left over (or two if the Joker is omitted). (see Variations, below) .