Queenside refers to the side of a chessboard where the queen starts the game. In standard chess notation, this is the left side for White and the right side for Black. The queenside includes the a, b, c, and d files, which are crucial for strategic play. In chess strategy, controlling the queenside can provide significant advantages, such as creating strong pawn structures and launching attacks. Players often aim to develop their pieces effectively on this side to gain control over the center and limit their opponent's options. Understanding chess openings and tactics on the queenside is essential for success in the game.