Plasma display panels (PDPs) have been developed so far mainly for office automation. In the past several years, 640×400-dot PDPs, corresponding to 12-inch-diagonal monochrome CRTs, have been put on the market by various manufactures as very thin display units containing integrated drive circuits. On the ohte hand, research and development on the color PDP have been being carried out to realize the color PDPs for graphic displays and flat large-size color TV receivers. This paper discribes both the principles of the monochrome PDPs on the market and the present status of color-PDP research.