The white and pink parts of fingernails differ in name and physical structure: the matrix forms the pink portions, or bases, of human fingernails, while cuticles comprise the top white parts and lunulas appear as the white semi-circles rising from nail bed bottoms. Human fingernails contain three distinct parts: the matrix, lunula and cuticle. Although forming the same body part, these segments play separate but equally important roles in facilitating some tasks and protecting fingers from harm; they may change color too, and also serve as indicators of health and well-being.
The matrix of each fingernail grows from the bottom of the nail bed, and starts forming below the surface of the skin. These parts appear in various shades of pink. In addition to giving nails a distinct color, they bear responsibility for generating new cells that help nails grow. They ultimately recycle and replace old cells, which rise to the surface as new cells develop.
Cuticles, the whitest parts of nails, form their topmost layers. Cuticles vary in length and thickness; some appear brittle and fragile, while others grow thick, which may indicate underlying health issues. Cuticles keep germs and bacteria from reaching the matrix.
All nails contain a lunula, which appears as a lighter colored half moon over the matrix. These parts bond with the matrix, and appear more vividly in some peoples' nails than others.