Electric charge is nothing but flow of electrons from one object to another. We all know that an atom is made up of electrons, protons and neutrons (look at the diagram on the right that explains the structure of an atom).
Electrons are negatively charged and protons are positively charged while neutrons are neutrally charged. At the same time the number of electrons and protons in an atom is always same. Now, if, by any means, few electrons can move away from the atom of object A to atom of object B, then object A will get positively charged due to deficiency of electrons while object B will get positively charged due to excess electrons. In such case object A will be called Positively Charged and object B will be called Negatively Charged. This is how electricity is generated.
What is Electrical Circuit?
Electrical circuit or power circuit is arrangement of electrically conductive path for flow and movement of electric charge or electricity. A home electrical wiring system is an example of electrical circuit.
What is an Electronic Circuit?
An electronic circuit is path made out of electronically conductive material such as metal, with electronic components on the path for controlled flow of electricity of electric charge. Electronic gadgets such as the TV, Computer, and Cell Phones etc all have electronic circuits.
How Electrical Circuit Works?
As I mentioned above, an electrical circuit or power circuit is arrangement of electrically conductive path for flow and movement of electric charge or electricity. To make an electrical circuit, we need a path for the electrons to flow, and a power-source to push them along. Electrons travel well through metals. Therefore, in an electrical circuit, a path is made out of thin metal in the form of wire. Power source for the circuit could be a switch from a home wiring or a battery. Let us take an example of a light-bulb connected to a battery. In order to glow the bulb, electrons have to be pushed out of the battery. This is done through electric field. The electrons then pass through the light-bulb, and back to the other end of the battery. During this process, the wire (normally tungsten) in the light-bulb get so hot that it glows and emits bright light. Similarly, electricity travels across your home wiring to your home appliances and helps them to work. This is how electrical circuit works.
How Electronic Circuit Works?
PCB(printed circuit board) of a computer, laptop, TV, cell phone etc are all examples of electronic circuit boards. These circuit boards have predefined metallic path for electricity to flow with electronic components on the way. These electronic components help to control the flow of electricity as and when required. Design of the circuit and arrangement of electronic components determines how an electronic appliance or gadget will work.