The purpose of the present paper is to provide an overview of the current biological and biomechanical knowledge on the hip. Various model formulations by researchers are discussed. Hip geometry is one of the crucial parts of human body movement. Researching on how various views of the hip is shown in different planes and how the forces act on the femur leads to learning of the various forces and torques acting on the hip joint. Hip anatomy, musculoskeletal model and FEA models are shown, forces acting on hip shown by various researchers are discussed and experimental studies are made. In addition, joint kinematics of the hip is also discussed to some extent.