RADIATIONÉ
is an wave that moves through space at a constant speed:  300,000,000 m/s
This wave is analogous to the ripples on a pond that propagate when the pondÕs surface is disturbed by a rock.  The difference is that instead of waves of water propagating through space, radiation involves waves of an electromagnetic field.


Radiation comes in many forms...
¥radio waves  ¥microwaves  ¥heat from a fire  ¥light
¥Ultraviolet rays  ¥X-rays  ¥Gamma rays