Light and Photons are essentially the same. Photons
are, in effect, units, or quantums of light that express particle-wave
duality. This means that a photon is at the same time a particle
and a wave. The term photon is often used when referring to the
intensity of a light source. The waves are usually used to identify
the type of light that is observed. This method involves the electromagnetic
spectrum. The wavelength of light determines its properties; frequency
is simply the number of waves per a given distance, usually a meter.
Light is a very strange entity. It does not have
mass in that classical sense, but in the modern sense in that it
has the ability to interact with other objects. Light travels always
at the same fixed speed of approximately 300,000 km/sec. To understand
what a mammoth speed this is, think of it as traveling around the
world about eight times in one second. Light is affected by gravity,
though it is not apparent on Earth. The curvatures present in the
universe slightly bend the light, often creating a mirror image
of an object. Gravity also has an obvious affect on light within
a black hole.
The only wavelengths the human eye sees are from
violet to red. When something is white, this means that all colors
are being reflected. When something is black, this means all colors
are absorbed. The three primary colors are yellow, red and blue.
This means that they are homogeneous in the sense that they are
not mixtures. These three main colors form all of the reflected
shades visible to the human eye.
Photons and other particles exhibit properties of light or, more
specifically, they act as waves. This information implies that particles
of considerable size, such as molecules, can be in two places or
more at once. Particles are actually present in two places at one
time or, in other words, they are in a state of superposition.