C.A.R.D.S. (alternately CARDS) is a simple RPG that uses a standard deck of playing cards (with three jokers) to handle all aspects of the game. The game is played with one GM and one to three players. Each participant selects a suit and takes the cards from that suit into their hands, and the GM adds the Jokers. The King, Queen, and Jack are played when a character uses their special ability during play. The Ace and 2 through 10 represent hit points and are discarded when a character takes damage. Jokers represent treasure.
Each suit held by a player represents a distinct "class" with a distinct special ability (Spades/Fighter; Hearts/Cleric; Clubs/Thief; Diamonds/Mage). If more than three players participate, a second deck of cards is used, suit by suit.
Play then progresses in a narrative fashion. When a conflict situation occurs a single card (Ace/2-10) draw from the GM plays against a picked card (Ace/2-10) from the appropriate player. The highest card wins. The cards are ranked in circular fashion, with an ace playing both high and low--that is, 2-9 takes an Ace, but Ace takes a 10. This "special case" nominally prevents players from simply picking 10 in every combat. The losing card is discarded, the winning card returns to the winner's hand.
Other rules control the use of special powers, the collecting of treasure, character death, and random "Quests" which play against a separate set of cards.
Note - the "acronym" C.A.R.D.S. apparently does not refer to anything; the rules use the acronym form and just CARDS both, apparently interchangeably.