1. A method of storing X-ray data of an object, acquired from mutually communicable X-ray detection modules, the method comprising: acquiring the X-ray data by using an X-ray detection module of the X-ray detection modules; transmitting all or some of the acquired X-ray data to other X-ray detection module, of the X-ray detection modules, that is different from the X-ray detection module that has acquired the X-ray data; and storing the all or some of the acquired X-ray data in a storage device of the other X-ray detection module.