Mammography is a special X-ray of the breast tissue, which can reveal abnormal growths even in the earliest stages of a tumor. Within recent years, digital technology has been applied to this process, eliminating the need for film, as the X-ray information is stored in the same way as a digital photograph. This drastically increases the speed of the process, as there is no film development time; also, the X-ray images can be enhanced and manipulated on a computer for more detailed and accurate viewing. Computer-aided detection (CAD) software is used as an additional support. It automatically detects suspicious regions on a mammogram, highlighting them for the mammographer. CAD is used as a "second reader" to detect missed breast cancers, providing one more layer of defense.