The human leg consists of several key components, including bones, muscles, tendons, and ligaments. The main bones are the femur, tibia, and fibula. The femur is the longest bone in the body, connecting the hip to the knee, while the tibia and fibula run parallel along the lower leg. Muscles in the leg are responsible for movement and stability. Major muscle groups include the quadriceps at the front of the thigh, the hamstrings at the back, and the calf muscles in the lower leg. Tendons connect muscles to bones, allowing for coordinated movement during activities like walking and running.