Things to know about electric current

Liquid, gas, solid substances are formed of molecules. As you know, one molecule is built up of several atoms. So again, when we dive into an atom we can see there are protons, neutrons and electrons. 

The electron carries negative electric charge and the proton carries positive electric charge. If an atom receives an extra electron, it will have a negative charge and when the atom losses one electron, then it will have a positive charge. 

Electrons are capable of travelling from one atom to another atom. In this manner, the electron flows through atoms through a conductor wire. It is called electric current.

The unit of electric current is ampere, so it is possible to measure electricity by connecting the ampere metre or ammeter to the series.