Originally, Naval war was fought by
ramming other ships and then
boarding them. In
Ancient Greece and
Rome, the ships were usually powered by
oars. During the
Middle Ages, the
cannon was invented. These could be shot at other ships from a great distance. Warships around this time also began to use
sails instead of oars for power. In the middle 19th century, ships began to be plated in
armor for protection.
Steam engines allowed them move while carrying the armor, and better ones soon made them much faster. These early warships, called
ironclads, are thought to have begun the type of Naval
warfare used today. Ships soon became much larger.