Wolf pack is actually the term added to the German strategy of submarine warfare by the English. Karl Donitz actually used the German term rudel. This term translates roughly to pack, which in turn became wolf pack in English.

The tactic was simple, place a group of U-boats in front of a convoy and attack. Pick off the slower ships and force the convoy to scatter. This would then reduce the effectiveness of the escorts and allow more ships in the convoy to be sunk.

Befehlshaber der Unterseeboote, BdU, Commander of Submarines, would issue orders to the U-boats where they were to meet. When the U-boats arrived on station they would contact each other to make sure there were enough in the area. When the number was sufficient they would decide how exactly to proceed with the attack.

The tactic worked so well that American submarines in the Pacific used it against the Japanese, with very effective results.

Wolf packs were defeated using aircraft to hunt submarines. They could be located by using a device know as HUFF DUFF. Since the attacking U-boats required excessive use of the radio to coordinate their attacks they were tracked using their own transmissions.

Today wolf packs are no longer used for submarines. However it is feared that a new style of wolf pack could be used to attack surface ships. The tactic would use many small craft to overwhelm the Aegis combat system. These small craft would them speed to their target and crash into them. The logistics of such an attack would actually be overwhelming for the attacker.