A condenser is a device that converts vapor into liquid by removing heat. It is commonly used in refrigeration and air conditioning systems to cool and condense refrigerants. The process involves the vapor passing through coils, where it releases heat to the surrounding air or water, resulting in condensation. In power plants, condensers play a crucial role in the steam cycle. After steam passes through a turbine, it enters the condenser, where it is cooled and transformed back into liquid water. This liquid is then pumped back into the boiler, completing the cycle and improving energy efficiency in systems like steam turbines and thermal power plants.