Applies to equipment and data related to the process ofteleradiotherapy, including patient image data used in relationwith radiotherapy treatment planning systems, radiotherapysimulators, isocentric gamma beam therapy equipment, isocentricmedical electron accelerators, and non-isocentric equipment whenrelevant.The object of this standard is to define a consistent set ofcoordinate systems for use throughout the process ofteleradiotherapy, to define the marking of scales (where provided),to define the movements of equipment used in this process, and tofacilitate computer control when used.