Types, or names

There are many types of electromagnetic radiation, all identical in essence. They are all periodically varying electric and magnetic fields. They all are wavelike.They all have the same velocity (in vacuum). They all appear dimmer at greater distances according to the formula (1/distance²). This last statement is the "inverse square law". (A light appears four times dimmer from twice as far away and nine times dimmer from three times further away, etc.) They differ only in the properties called ``wavelength'' and ``frequency.''