Color reflected color depends upon the viewing angle. Numerous scientists have carried out research in butterfly wings and beetle shells, including Isaac Newton and Robert Hooke. Since 1942, electron micrography has been used, advancing the development of products that exploit structural color, such as "photonic" cosmetics. Color Color (American English), or colour (Commonwealth English), is the characteristic of human visual perception described through color "categories", with names such as red, orange, yellow, green, blue, or purple. This perception of color derives from the stimulation of cone cells in the human eye by electromagnetic radiation in the visible spectrum. Color categories and
Orange (colour) series, wear orange swimsuits to make them stand out. Orange astronaut suits have the highest visibility in space, or against blue sea. An aircraft's two types of "black box," or flight data recorder and cockpit voice recorder, are actually bright orange, so they can be found more easily. In some cars, connectors related to safety systems, such as the airbag, may be coloured orange. The Golden Gate Bridge at the entrance of San Francisco Bay is painted international orange to make it more visible in the fog. Next to red, it is the colour most popular for extroverts, and as