Computed Tomography (CT), originally known as computed axial tomography (CAT) and body section roentgenography, is a medical imaging method employing tomography where digital geometry processing is used to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation. The word "tomography" is derived from the Greek tomos (slice) and graphia (describing). CT produces a series of axial images which can be manipulated, through a process known as windowing, in order to recreate the image in a different plane.