The authors of the work, using numerous English and a number of German sources, set out the development of the combat activities of German submarines throughout the World War, starting with the first departure of boats from the base on Heligoland on August 2, 1914 for sentinel service and ending with the surrender of the German fleet to the Allies. At the same time, the gradual development of anti-submarine weapons and anti-boat techniques, their use by the British fleet and cases of boat deaths are described.