This applet illustrates the broad range of phenomena covered by the electromagnetic spectrum and generally known as light. The section we can actually see, visible light, is a very small part of the whole.
In this applet, you can click on the wavelength/frequncy scale and change the wavelength and frequency by draggin the mouse around. You can also change the wavelength by using the arrow keys on your keyboard. Holding the shiftkey down while pressing the left or right arrow keys changes the wavelength by a factor of 10.
© W. Bauer, 1999