what is the skin that grows under the nail
Nail (anatomy) The nail bed is the skin beneath the nail plate.[8][unreliable source?] Like all skin, it is made of two types of tissues: the deeper dermis, the living tissue which includes capillaries and glands,[9][unreliable source?] and the epidermis, the layer just beneath the nail plate, which moves toward the finger tip with the plate. The epidermis is attached to the dermis by tiny longitudinal "grooves"[5] called matrix crests (cristae matricis unguis).[3][9] In old age, the nail plate becomes thinner, and these grooves become more visible.[5]
Lunula (anatomy) The lunula, or lunulae (pl.) (from Latin, meaning 'little moon'), is the crescent-shaped whitish area of the bed of a fingernail or toenail. The lunula is the visible part of the root of the nail.