Arms are the upper limbs of the human body, extending from the shoulders to the hands. Each arm consists of three main parts: the upper arm, forearm, and hand. The upper arm contains the humerus bone, while the forearm is made up of the radius and ulna. Arms are essential for various functions, including lifting, reaching, and manipulating objects. The structure of the arm includes muscles, tendons, and ligaments that enable movement and strength. The shoulder joint allows for a wide range of motion, while the elbow joint provides bending and straightening capabilities. Overall, arms play a crucial role in daily activities and interactions.