Reversi:

The object of the game is to own more pieces than your opponent when the game is over. The game is over when neither player has a move. Usually, this means the board is full.

Each reversi piece has a red side and a green side. On your turn, you place one piece on the board with your color facing up. You must place the piece so that an opponent's piece, or a row of opponent's pieces, is flanked by your pieces. All of the opponent's pieces between your pieces are then turned over to become your color.

Reversi and Othello are names for a strategic board game which involves play by two parties on an eight-by-eight square grid with pieces that have two distinct sides. Pieces typically appear coin-like, with a light and a dark face. The object of the game is to have the majority of your pieces on the board at the end of the game by turning as many of the opponent's pieces over as you can.

Game Rules

The 2 players take turns to place a disc on the board. Red player starts the game.
A disc must always be placed near one or more of the opponent's discs. The objective is to enclose your opponent's discs by placing your discs at each end of a row of one or more of your opponent's, thus making them yours.
If you cannot place a disc in your turn the opponent moves again.
If no one can move the game ends.
The game continues until the board is filled with discs and the winner is the one with the majority of the discs. If both players have the same number of discs, the game is a draw.

Play

Each of the two sides corresponds to one player; they are referred to here as light and dark after the sides of Othello pieces, but "heads" and "tails" would identify them equally as well, so long as each marker has sufficiently distinctive sides.

Originally, Reversi did not have a defined starting position. Later it adopted Othello's rules, which state that the game begins with four markers placed in a square in the middle of the grid, two facing light-up, two pieces with the dark side up. The dark player makes the first move.