A mammogram is a two-dimensional, black-and-white X-ray of the breast that is done to screen for breast cancer and to investigate lumps that can be felt during a breast exam. A mammogram can also detect tumors or abnormal areas that are too small to be felt with the hands.
A digital mammogram is done in the same way as a standard mammogram. A digital mammogram allows your doctor to view different parts of the breast without taking more images.
WebMD Medical Reference from Healthwise