Dreadnought

• Considered the ultimate naval weapon, the dreadnought was first launched by the British in 1906. Protected by up to 12 inches of steel armor, the dreadnought could reach a speed of 21 knots -- two knots faster than any other ship in use. Dreadnought firepower came in the form of 10, 12-inch guns distributed between five revolving turrets, meaning it could fire heavier shells on target than any other ship. The dreadnought, however, played a minor role in the war as many commanders believed them too valuable to risk. The Germans used their dreadnought, Prinzregent Luitpold, at the Battle of Jutland in 1916.
  
  

Battle Cruisers

• Battle cruisers were also involved in the Battle of Jutland and other major battles of World War I. This British invention was fitted with large-caliber guns but contained less armor as a means of increasing its speed and range. This allowed the battlecruiser to take on larger ships but also enabled it to make a quick getaway, if necessary. The battlecruisers did, however, have defensive weaknesses. The British ship, Invincible for example, exploded and sank after a hit from a German ship at the Battle of Jutland.
  
  

Destroyers

• First developed in the late-19th century, destroyers were small, fast warships, equipped with torpedoes. They filled numerous roles during World War I, from supporting main fleets to protecting home waters from attack. As the destroyer was relatively quick and cheap to build, they were commonplace among the various navies of World War I: 450 served with the British Navy, for example, and the Germans deployed more than 230 throughout the course of the war.
  
  

Submarines

• Never used before in conflict, submarines quickly came to dominate naval warfare in World War I. Although early submarines were slow and only able to dive for a couple of hours, they became technically more advanced as the war progressed, specifically with range, speed and armament. The Germans were particularly successful at submarine warfare, sinking 230 Allied submarines in February 1917 alone. Equipped with torpedoes, submarines posed a significant threat in the ocean and became as feared as the dreadnought.