PCM, or Phase Change Material, is a substance that can absorb, store, and release thermal energy during the process of melting and freezing. These materials are used to regulate temperature in various applications, such as building materials, clothing, and electronic devices. By changing from solid to liquid and back, PCM helps maintain a stable temperature, improving energy efficiency. Common types of PCM include paraffin wax and salt hydrates. They are often incorporated into products to enhance comfort and reduce energy consumption. As they change phase, they can effectively manage heat, making them valuable in both residential and industrial settings.