Battleship was one of the earliest games to be produced as a computer game, with a version being released for the Z80 Compucolor in 1979. Many computer editions of the game have been produced since.
In Clubhouse Games for the Nintendo DS, Battleship is known as Grid Attack. It is played on an 8×8 grid, and includes slight variations, such as 4-player gameplay, various ship sizes and shapes, as well as the option to make the ships touch each other. Iterations of Battleship appear as applications on numerous social networking services.
The game is played on four grids, two for each player. The grids are typically square – usually 10×10 – and the individual squares in the grid are identified by letter and number. On one grid the player arranges ships and records the shots by the opponent. On the other grid the player records his/her own shots.
Before play begins, each player secretly arranges their ships on their primary grid. Each ship occupies a number of consecutive squares on the grid, arranged either horizontally or vertically. The number of squares for each ship is determined by the type of the ship. The ships cannot overlap (i.e., only one ship can occupy any given square in the grid). The types and numbers of ships allowed are the same for each player. These may vary depending on the rules.
After the ships have been positioned, the game proceeds in a series of rounds. In each round, each player takes a turn to announce a target square in the opponent's grid which is to be shot at. The opponent announces whether or not the square is occupied by a ship, and if it is a "miss", the player marks their primary grid with a white peg; if a "hit" they mark this on their own primary grid with a red peg. The attacking player notes the hit or miss on their own "tracking" grid with the appropriate color peg (red for "hit", white for "miss"), in order to build up a picture of the opponent's fleet.