For many centuries people were unaware of the existence of electricity. And lightning was seen as a manifestation of inexplicable divine forces. How could the people living surrounded by electric and magnetic fields completely to ignore them? This happened because of free electricity in nature is very rare. However, the familiar properties of matter, as the force of elasticity, friction, even the power of our muscles, are a manifestation of the electromagnetic force.
The ancient Greeks noticed that if you RUB a piece of amber with wool, it will have the ability to attract light objects. Amber in Greek is called the electron, and therefore the substance contained in this condition became known as electrified. Why this phenomenon occurs, the Greeks to explain could not.
The first steps to understanding the nature of electricity were made in the mid-eighteenth century, when French physicist Pendant discovered the law of interaction of electric charges. Electric charge occurs when the excess or deficiency of electrically charged particles. Any body charged negatively, such as a rain cloud, comb, glass rod, lack of protons, since it is dominated by electrons. Conversely, body, positively charged, contain an excess of protons. When the total number of protons and electrons equally, the body has no electric charge.
Ordered the free movement of electrically charged particles is called an electric current. In metal conductors such as free charge carriers are electrons, in solutions of electrolytes - ions (electrolyte is a liquid that can conduct electric current).
At the end of XVIII century Italian physicist Alessandro Volta created the first current source and gave physicists the opportunity to conduct experiments with electric current.