A limb is a jointed appendage of the body, typically used for locomotion (running, walking, climbing, swimming), grasping or climbing. Limbs are found in all animals, including humans.

The number of limbs present in any animal depends on their specific habitat and lifestyle. For instance, a bird has long prehensile forelimbs that are adapted for grasping and climbing. Likewise, a fish has a streamlined forelimb that is adapted for flight and swimming.

Tetrapods, vertebrates that include all amphibians, reptiles, birds and mammals, have four limbs. Each limb is made of similar sets of bones and is homologous with the others.

Humans have 248 limbs: 101 in the head, arms and shoulders and 100 in the legs.

There are 30 bones in the lower limbs: the femur, patella, tibia and fibula. There are 18 vertebrae in the spine and 11 ribs.

The upper limb is made up of three parts: the arm, the forearm and the hand. It contains 30 bones and many nerves, blood vessels (arteries and veins) and muscles.

The body consists of more than 650 different muscles, which are attached to the skeleton by tendons. The muscles are responsible for moving the body and performing other functions.