The arms and legs together are collectively called the "limbs" of the human body. More specifically, the arms are referred to as the upper limbs or forelimbs, and the legs are referred to as the lower limbs or hindlimbs. These paired limbs work together for movement, locomotion, and interaction with the environment. The limbs include the bones and muscles that form the appendicular skeleton, responsible for activities such as walking, running, grasping, and manipulation.
In summary:
- Arms and legs collectively = limbs
- Arms = upper limbs / forelimbs
- Legs = lower limbs / hindlimbs
This terminology is commonly used in anatomy and biology.