The dorsum refers to the upper or posterior surface of a body part. It commonly refers to the top surface of the hand or the upper surface of the foot. The dorsum is characterized by its distinct anatomical features, such as the knuckles and veins on the back of the hand, or the prominent bones and tendons on the upper surface of the foot. It serves as a functional region involved in various movements and interactions with the environment, playing a crucial role in tasks such as grasping, manipulating objects, and providing stability and support during locomotion.