Armored cruisers could be considered the first step to the battle cruiser. In theory, they were both designed to do the same job: scout for the fleet, destroy enemy cruisers, and operate independently of the battle fleet. Armored cruisers were larger and faster than battleships, but more lightly armed and armored. The larger size came from having larger engines for more speed. Battle cruisers were larger and faster than battleships, had the same armament as battleships, but were lightly armored. Battle cruisers were susposed to be used just like the armored cruisers, however, with those big guns Admirals just couldn't resist putting them in the battle line along side the battleships. The results were disasterous for the battle cruisers. Britian lost three in one day at Jutland during WWI, and in WWII the Bismark finished off the Hood in only 5 minutes .
The German pocket battleships were officially called Armored Ships by the Germans and were designed mainly to be commerce destroyers.