New technologies in refrigeration include solid-state refrigerators and refrigerators that use magnets.

• Solid-state refrigerators use the refrigerator's entire surface to slowly get rid of the heat. Solid-state refrigerators are also free from harmful materials and loud operations.
• Refrigerators that use magnets provide a vibration-free, silent, environmentally friendly refrigerator. It uses a magnetocaloric heat pump (using a material that heats up in a magnetic field and cools down when it is not) with water-based coolant. It also uses up to 35 percent less power than traditional refrigerators.

Refrigeration is the action of creating cooling conditions by removing heat. It is used for preserving food by slowing bacteria growth.

• Around 1000BC, the Chinese used to cut and store ice.
• Five hundred years later, the Egyptians and Indian...