Also known as Othello. It's a two-player strategy board game played on an 8x8 grid. The goal is to have the majority of your colored discs (either black or white) on the board when the game ends. Players take turns placing their discs on the board, sandwiching the opponent's discs to flip them to their color. Reversi is known for its simple rules but challenging gameplay, making it a popular classic board game.