The beam of electromagnetic radiation visible to the human eye. In a broader sense to include within a larger (IR) and small-wavelength (UV) radiation as well.
The light features three principal defining aspects:
intensity or amplitude, that man fényerőként, fényességként detected,
frequency (and in this context is the wavelength), which color on the human senses, and
polarization, ie the direction of the electromagnetic vibrations, so that ordinary people can not perceive under normal conditions, but as certain insects do.

Earth bathed in sunlight. I wonder how to utilize this organism, and how can they even lit?

In light of the sun nurtures life. So in the light of life in all areas is essential: the vital processes required for energy supplies, the most important medium of perception, our regulator. The light and the interaction between living organisms and complex biological and physical processes through. The interaction is very diverse: the conversion of light energy, light perception or even the lighting of many organisms on its own very interesting phenomenon. The performance of these areas presents the typical process, describes the specificities and the general regularities. At the same time it also tries to give a picture of how individual molecules are able to perform complex tasks that are in our daily lives can only be achieved through a complex machinery.

The visible light sensors, the most important medium, too. The wide range of physical origin indicator organisms are used, there are others - are exceptional, although they go - for which the light is not even relevant. Yet, generally speaking, the light is the most widely used source of orientation. The information in our environment as we get information that the scattered (or even released), visible light sensors. Almost every living thing "see", even though the plants as well. Now, in vertebrates, particularly human vision elements are considered relevant to the exhaustive.

The light is the most effective highlighting tool. The artist's award directs the viewer with her eyes, you want it. Titus just as Rembrandt's portrait of the reader's face and his hands made light, that primarily attract viewers' attention.