These are appliances used for disabled or older persons for propagation. Mobility aids help in supporting body weight and thus make stability during walking. Selection of a mobility aid depends upon the degree of relief in weight bearing, strength of the limb that uses it, co-ordination of the person and acceptance etc. Independent mobility aids are parallel bars, walking frames, rollators, waling sticks and tripods and tetrapods. Crutches are advocated for lower limb weakness or inability for performance. Other mobility aids are tricycles and wheelchairs.