Why warships carried conspicuous deck markings

Why did Italian warships carry red-and-white diagonal stripes, and did other navies use similar markings?

They were aerial recognition markings, comparable to national emblems, turret numbers, and large flags used by other fleets to prevent friendly attack.

Italian red-and-white diagonal stripes helped aircraft identify friendly warships. Bismarck carried a large Nazi emblem on her bow for the same purpose. American battleships used flags or identifying numbers painted on turret tops. Large Royal Navy ensigns provided another conspicuous recognition aid.