A nail is a keratinized structure that protects the fingertip and the adjacent tissues from injuries. The epithelial matrix cells attached to the nail bed gives rise to the formation of nail. A healthy nail gives translucent pinkish hard but flexible smooth and shiny appearance. The growth rate of nail is more in children than adults. Structurally Human nail is composed of many parts which are reviewed in this article and performs many functions. Human nails are good indicator and very helpful in diagnosis of many diseases.