The TAOS TCS230 is a small, highly integrated color sensing device packaged in a clear plastic 8-pin SOIC. It reports, as analog frequency, the amount of shortwave (blue), mediumwave (green), longwave (red), and wideband (white) optical power incident onto the device. It can be used in a variety of color sensing applications. Details of the device can be found in its datasheet. This white paper details the concepts and calculations involved in color sensing using the TCS230.