Basic electricity

nature of matter
The small particle that can exist is known as molecule. In general ,the molecule is made up of smaller particle known as atom. if we split up the atom, we find that it si composed basically of two particle : the electron and proton
Current is the flow of electron

voltage and current
If we take a source of electricity such as a battery, there is a certain force tending to send a current or flow of electrons through an external circuit between the two terminals . The force is called the voltage of the battery.

units

The unit of the voltage is volt
The unit of current is ampere
The unit of resistance is ohm