This technical report explains differences in definitions of the terms used in the flat panel display field such as liquid crystal displays (LCD)@ plasma displays (PDP)@ and organic light emitting diode displays (OLED). The definitions of technical terms are individually specified in the different standards: ?C Liquid crystal display: IEC 61747-1 ?C Plasma display: IEC 61988-1 ?C Organic light emitting diode display: IEC 62341-1-2. This report explains the background and reasons for the differences@ but does not introduce new definitions or terms.