Introduction an electricity.

Electricity is a energy source utilized by an electrical equipment. Electricity is meant for flow electrons present in all matter e.g.copper, aluminium. All matter is made up of atoms ,which has a center called a nucleus. In a nucleus contains protons charged positively  and uncharged  neutrons .The nucleus of an atom surrounded by negatively charged particles called electrons.In atom number of positively charged  protons is usually equal to the number negatively charged  electrons are balanced.If balancing force between protons and electrons is upset by an outside force i.e. applying voltage an atom may gain or lose an electrons.When an atom lost electrons is free to move constitutes an electric current.