Condenser is a refrigeration component which has function to condense the refrigerant from gas phase to liquid phase. To Condenser gas phase to liquid need remove heat. The heat from condenser is removed to anything surrounding the Condenser, in common Air Conditioner usually remove heat to air surrounding the condenser. 

Condenser is put outside the room or building that will be cooled. Common Air Conditioner, Condenser is a Heat Exchanger which consist pipe and fins. Air is flown to fins of heat exchanger then the heat transfer occur from condenser to the air.