Solitaire is a game where players build up the cards in suit and rank from Ace to King. The game is played using one deck of 52 playing cards. Solitaire games can be played by a single player or with multiple players if more than one deck of cards are available (one for each player).
The name "solitaire" comes from solitaires - stones that are set in rings on either side of the Queen's crown, so it doesn't fall off when she bows her head. The name solitaire became associated with this game in the 17th century when Louis XIV of France wore a ring on his smallest finger. He would play several solitaire games at once, seeing which one he could complete first while simultaneously playing another game.