How does electricity created?

In a nutshell

Electricity is created when particles become charged. Some

are negatively charged (electrons), and some are positively 

charged (protons).

These opposite charges attract, whereas particles with 

similar charges repel each other.

Electrons of many elements, particularly metals, are easily 

knocked off from their parent atoms and can wander freely 

between atoms. If a state of unbalanced charges exists, then 

a necessary condition to create an electric current also 

exists. However, the flow of electric current cannot take 

place 

until the circuit is completed.