Light is a form of energy that allows us to see what surrounds us. It is all electromagnetic radiation that propagates in wave forms in any space, it is capable of traveling through a vacuum at a speed of approximately 300,000 kilometers per second. Light is also known as luminous energy. There are different light sources that can be classified into natural and artificial. The Sun is the main natural and important source of light on Earth. As for artificial sources, we would be talking about the electric light of a light bulb, the light of a candle, oil lamps, among others.

Light is emitted from its sources in a straight line and in all directions, spreading over a larger and larger area as it travels. If something gets in the way of it, a shadow is formed in the place where the light does not pass; for example, in opaque bodies, light tends to pass easily through glass or water.

Like all waves, light undergoes the phenomena of reflection and refraction. The reflection of light is the change experienced by the light ray when it strikes the separation surface of two different media without leaving the medium through which it propagates. Mirrors reflect light in a normal way, the light bounces back in the same way it arrives and as a result an image can be seen in the mirror.

The refraction of light is the change of direction of a light ray when passing from one medium to another of different density, through which it travels at different speeds. Lenses are pieces of glass that work by refracting light.

Light has an important effect for everyone, thanks to it we can see objects, our companions, signs and symbols, among other things. Light can change the properties of bodies; For example, a sheet of white paper, when exposed to sunlight for a certain time, turns yellowish.

Light allows plants and animals to develop processes to obtain energy, human beings have also learned to use it to achieve a better way of life, we use it to heat our homes, cook, etc.