A plaster cast is a hard protective shell made from a mixture of plaster and water. It is commonly used in medicine to immobilize broken bones or injured limbs, allowing them to heal properly. Once applied, the plaster hardens and forms a rigid structure that keeps the affected area stable. Plaster casts are typically used in conjunction with other medical practices, such as X-rays to diagnose fractures. They can be customized to fit the shape of the limb and are often lined with soft padding for comfort. After healing, the cast is removed, usually with a special saw.