Icon wiki:
Greek , eikon, "image") is an image, picture, or representation; it is a sign or likeness that stands for an object by signifying or representing it, or by analogy, as in semiotics; in computers an icon is a symbol on the monitor used to signify a command; by extension, icon is also used, particularly in modern popular culture, in the general sense of symbol â i.e. a name, face, picture or even a person readily recognized as having some well-known significance or embodying certain qualities.
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Light wiki:
>For other uses, see Light (disambiguation). Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific setting, electromagnetic radiation of any wavelength. The three basic dimensions of light (i.e., all electromagnetic radiation) are:intensity (or brilliance or amplitude), which is related to the human perception of brightness of the light,frequency (or wavelength), perceived by humans as the color of the light, andpolarization (or angle of vibration), which is not perceptible by humans under ordinary circumstances. Due to wave-particle duality, light simultaneously exhibits properties of both waves and particles. The precise nature of light is one of the key questions of modern physics.
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