secret+methods
131Industrial espionage — Teapot with Actresses, Vezzi porcelain factory, Venice, ca. 1725. The Vezzi brothers were involved in a series of incidents of industrial espionage. It was these actions that led to the secret of manufacturing Meissen porcelain becoming widely… …
132Light-emitting diode — LED redirects here. For other uses, see LED (disambiguation). Light emitting diode Red, pure green and blue LEDs of the 5mm diffused type Type Passive, optoelectronic Working principle Electr …