Light, also known as visible light, is simply a small fraction of the electromagnetic waves spectrum generated by every particle. What this means is that light are simply particles/waves, more on this later, right now we'll just consider them as particles of photons. vibrating at a certain frequency that our eyes can pick up as visual signals to send to our brain. In this case these particles would be the photons. A typical human eye will respond to wavelengths from about 390 to 700 nm. These values would mean different colors to us. So yes a designer's concept of colors can be in #00FF00 or #0000FF also known as hex color codes, but in a scientific point (physics rather) colors are just caused by how our eye pick up photons vibrating at different wavelengths. 390nm would be violet while it gradually scales to where 700nm would be red. It is often theorized that different animal/insects can perceive a wider range of wavelengths as light and thus are able to see colors unknown t...