When do we see the spectrum of light?

Sir Isaac Newton of Cambridge University in England, first uncovered the secrets of how light is divided up. we think of ordinary light as being white, but really light is a mixture of red, orange, yellow, green, blue and violet, when sunlight strikes the beveled edge of a mirror, or the surface of a soap bubble, we can see the different hues in light .what actually happens is that the white light is broken up into the different wave lengths that are seen by our eyes. These wave lengths form a band of parallel stripes, each hue grading into the next to it. This band is called a spectrum. In a spectrum the red line is always at one end and the blue and violet lines at the other.