The radiator is located at the front of the car, just behind the condenser, and is the most important component of the cooling module because it keeps your engine from overheating.  The radiator is made up of a radiator core, along with two plastic side tanks, and all the necessary connections and attachments.  The radiator core is made up of a network of fins and tubes that run either horizontally or vertically, depending on application.  As the coolant/water mixture enters the radiator, it is run through a system of ultra-thin tubes and as the mixture flows through these tubes, air is run over the mixture, cooling the liquid before it exits the radiator.  When the liquid exits the radiator it is sent back to the engine to absorb heat, in turn cooling the engine and restarting the entire process.