Black means black in Chinese. Black is an English word, noun, adjective and verb. When it is used as a noun, it is translated into "Heihe"; Tuojiang (river name), black (name), black; Black people; Black pigment ",translated as" black "when used as an adjective; Black; Ugh. "

Black is defined as basically no visible light entering the visible range. Contrary to white, it means that all the light in the visible spectrum enters the visible range at the same time.

If the pigment absorbs all visible light in the spectrum and does not reflect any color light, the human eye will feel black. If the pigments of the three primary colors are mixed in a proper proportion, and the reflected colored light is minimized, the human eye will also feel black. So black can be caused by insufficient light (night) or by absorbing all colors of light (black pupil).