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Looking at either of a light wave's two disturbances, the disturbance varies in a fashion like that shown in the image above. This type of repeating variation is called sinusoidal. The separation distance between peaks of the repeating variation is called the wave's wavelength. The number of full variations (or cycles) that pass by a stationary point of observation per second is called the wave's frequency. It is relatively easy to show that the speed of a light wave is equal to its frequency times its wavelength. That speed, in outer space or in air, is a constant, and is equal to 186,000 miles per second, or 300,000 kilometers per second.
When we talk about "types" of light, we are really only talking about "ranges of frequencies" of light. For example, x-rays are just light waves whose frequencies are substantially greater than any frequency a human eye could perceive. Similarly, radio waves are just light waves whose frequencies are substantially less than any frequency a human eye could perceive.
Because a light wave doesn't require a medium, light can travel an arbitrarily large distance without "getting tired". Water waves, by comparison, peter out over a relatively short distance, because energy in the wave is required to jiggle the water. With light, there is nothing to jiggle: it just continues to "create itself" as it moves along. We say that light is "self-propagating": it keeps itself going.
From a classical perspective, a light wave is said to be composed of two disturbances. The two disturbances are electric and magnetic in nature, and neither is considered to be material, or mass like, so light waves require no medium. Both of a light wave's disturbances vary in directions perpendicular to the movement of the wave, so the light wave is said to be transverse. Because of the nature of a light wave's two disturbances, we also refer to a light wave as electromagnetic radiation.
The easiest way to visualize an ordinary wave is to watch water "undulate", or jiggle, when disturbed. The surface of the disturbed water forms a wave, and that disturbance typically moves as an assembly on the surface of the water. The underlying water, the medium of the wave, typically doesn't move much from its pre-disturbed location: it just jiggles in such a way that the wave disturbance on the water's surface moves outward from the location where the wave originated.
From a classical perspective, that is from the perspective of a physicist working just prior to 1900, light is exclusively considered to be a wave, not a particle.
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