Orthotic devices come in many shapes, sizes, and materials and fall into three main categories: those designed to change foot function, those that are primarily protective in nature, and those that combine functional control and protection.

Rigid orthotic devices are designed to control function and are used primarily for walking or dress shoes. They are often composed of a firm material, such as plastic or carbon fiber. Rigid orthotics are made from a mold after a podiatrist takes a plaster cast or other kind of image of the foot. Rigid orthotics control motion in the two major foot joints that lie directly below the ankle joint and may improve or eliminate strains, aches, and pains in the legs, thighs, and lower back.

Soft orthotics are generally used to absorb shock, increase balance, and take pressure off uncomfortable or sore spots. They are usually effective for diabetic, arthritic, and deformed feet. Soft orthotics are typically made up of soft, cushioned materials so that they can be worn against the sole of the foot, extending from the heel past the ball of the foot, including the toes. Like rigid orthotics, soft orthotics are also made from a mold after a podiatrist takes a plaster cast or other kind of image of the foot.

Semi-rigid orthotics provide foot balance for walking or participating in sports. The typical semi-rigid orthotic is made up of layers of soft material, reinforced with more rigid materials. Semi-rigid orthotics are often prescribed for children to treat flatfoot and in-toeing or out-toeing disorders. These orthotics are also used to help athletes mitigate pain while they train and compete.