This article is the first of a three-part series that deals with color and how it applies to electronic imaging. This first installment addresses color fundamentals, laying ground for the following articles, which are about optical scanning, data compression, and hardcopy output, including conventional 4-color printing. In this article the physical and physiological aspects of color are discussed. Followed by an introduction of color standards and mathematical models used to describe color. Color matching and calibration are discussed, methods whereby color can be specified and reproduced with predictable results. Limitations in color reproduction and display are identified, and a new means employed by some manufacturers to stabilize the CRT display process are explained. The article concludes with a brief introduction to color applications, a subject to be addressed by future articles.