A battleship is a large armored warship with a main armament (main weapons) consisting of heavy caliber guns. Battleships are larger, better armed and armored than cruisers and destroyers. After the old wooden sailing ship of the line became obsolete around 1870, battleships were the new capital ships, the largest armed ships in a fleet. They were used to take command of the sea, and represented the apex of a nation's naval power.