Abstract: A bar code scanner having light sensitive means for detecting black and white regions of a bar code and having circuit means for translating the light pulses into digital signals. The scanner system has circuit means responsive to bar codes employing bars of only two different widths, specifically wide bars and narrow bars. The scanner has automatic level control circuitry and has means for detecting the bar code substantially independent of the angle and speed of scan within desired limitations. The scanner also has built-in error checking and warning devices as well as an automatic clear system for clearing errors. The data developed by the scanner is then transferred by suitable circuitry to a data collection and utilization system.