The device needed in cryodesiccation or freezing certain material is widely known as freeze dryer. The process of dehydration that is mostly used in the preservation of fragile material is called cryodesiccation. The process of freeze-drying makes the material more suitable for transporting. Freeze-dryer helps in freezing materials and then reducing the pressure to allow the frozen water to change from solid to gas state directly. The first freeze-dryer helped in the development of anti-rabies vaccine by making the live rabies virus freeze.