Cryogenics is the study of the production and behavior of materials at extremely low temperatures, typically below -150 degrees Celsius (-238 degrees Fahrenheit). It involves the use of cryogenic liquids, such as liquid helium or liquid nitrogen, to cool substances and explore their physical properties. Applications of cryogenics include superconductivity, medical technologies like cryopreservation, and the storage of liquefied gases. The field plays a crucial role in various scientific and engineering disciplines.