Battleship (also known as Battleships or Sea Battle) is a strategy-type guessing game for two players. It is played on ruled grids (paper or board) on which each player's fleet of warships are marked. The locations of the fleets are concealed from the other player. Players alternate turns calling "shots" at the other player's ships, and the objective of the game is to destroy the opposing player's fleet. Battleship is known worldwide as a pencil and paper game that dates from World War I. It was published by various companies as a pad-and-pencil game in the 1930s and was released as a plastic board game by Milton Bradley in 1967.

Source: Wikipedia