The use of computers in medicine is now widespread and accepted. A primary problem in computer utilization is the input. Optical scanning is presented as a computer input mechanism. Three practical applications of optical scanning, used as examples, are recording of (1) patient diagnosis, (2) laboratory data, and (3) results from a comprehensive ophthalmologic examination. When properly utilized, optical scanning provides one effective and efficient means of aiding the process of input for eventual information retrieval and data analysis in medicine.