Difference between Turbojet and Turbofan

A turbojet engine is a gas turbine engine that generate thrust through its exhaust .whereas a turbofan engine generates thrust through its own fan. An additional fan at the front of a turbofan engine draws air from the outside and blows it through the engine's core where combustion occurs before returning it to the outside to generate forward thrust. This allows for more airflow into and out of the engine than a turbojet can provide on its own, resulting in more efficient operation.