Chess is a two-player strategy board game played on a chessboard, a checkered gameboard with 64 squares arranged in an 8×8 grid. The game is played by millions of people worldwide. Each player begins with 16 pieces: one king, one queen, two rooks, two knights, two bishops, and eight pawns. Each of the six piece types moves differently, with the most powerful being the queen and the least powerful the pawn. The objective is to checkmate the opponent's king by placing it under an inescapable threat of capture. To this end, a player's pieces are used to attack and capture the opponent's pieces, while supporting each other. In addition to checkmate, the game can be won by voluntary resignation of the opponent, which typically occurs when too much material is lost or checkmate appears inevitable. There are also several ways a game can end in a draw.
Note: this information has been paraphrased from Wikipedia.