Electromagnetic fields

The natural environment is characterized by the presence of radiation coming from numerous sources. The electric and magnetic phenomena of cosmic and seismic nature, or even artificially generated, have important impacts on the vital processes. Thus it is necessary to relate and study the connection between the natural electromagnetic phenomena with the natural one. In fact electromagnetic pollution is also determined by atmospheric conditions in the natural electromagnetic field and by the "invasion" of a natural field by a artificial one.

Electromagnetism is indicates the electric and magnetic phenomena, of natural or artificial nature, as a whole, and the relation existing between them.
At the end of the last century Faraday and Maxwell elaborated the first complete theory on electromagnetism. It went to replace the existing concept of "force" with that of "field." A field is at the same time the condition of space capable of producing a force and the action of the force being produced, and it is generated by each single charge.

The main factor f this research was the concept of light as an electromagnetic field (EMF), propagating into space like waves. Now while classical physics conceived space as an " emptiness in which solid bodies move," this new concept applied the notion of waves. Maxwell thought that the same way waves propagate in the water, electromagnetic field create a state of mechanical tension, capable of moving in a thin element which fills up all space. He imagined that this element (which we will call ether) could be crossed by elastic waves (electromagnetic waves: EM).
Later Einstein out dated this concept considering the EMF (electromagnetic fields) physical entities which cannot be explained mechanically, and conceived the modern interpretation of electromagnetic radiation.

Fields, waves, and radiation are the same thing, different terms to indicate forms of energy which propagates in space. All EM waves, in electric and magnetic fields, are oscillating and differ from each other only in frequency.
Visible light is part of the Em waves, but just constitutes a small fraction of the electromagnetic spectrum. At the top of the spectrum are UVA rays and Gamma rays and at its bottom are infrared rays and radio waves.

The fields (or waves) are classified according to their frequency, which consists of a number of oscillations the wave performs per second. Low frequencies are between 0 and 10,000 Hertz (10 Khz), while high frequencies are included between 10 Khz and 300 Ghz.