Finger belly is broadly defined as the ventral portion of the finger, and narrowly defined as specifically the ventral portion of the terminal phalanges of the finger. Broadly speaking, the digitus, the ventral (or palmar) portion of each knuckle of the finger, has thick skin, rich in sweat glands, but without hair or sebaceous glands. The stratum corneum is thicker, there is a thick fat pad under the skin, and there are a lot of vertical fibrous intervals, connecting the skin with the phalanges, tendon sheaths and other deep tissues, coupled with the distal interphalangeal joints transverse stripe also has a fibrous septum under the skin, making the finger belly become a closed gap, which prevents the skin from slipping, in order to adapt to the grip, pinch action and the need for direct contact with the object, to maintain a stable grip. Narrowly is the daily life refers to the fingers of the last section of the abdomen, that is, people often say “finger belly”. Finger the last section of the palm surface of the soft meat part of the hand, and the opposite of the nail. Fingerprints on the surface of the finger belly, each person’s fingerprints are unique.