What is a Switch?
A switch is an electrical component which can make or break an electrical circuit automatically or manually.
Components of electric circuit
In our house, all the switches connecting different appliances are present on a switchboard. And all these appliances work because of some circuit being completed.
Consider the simplified version of an electric circuit for any appliance in our house.
Electric circuit
 This electric circuit has three components:
- Transformer
- Switch
- Appliance
When we switch on any appliance, the current flows through the circuit and the appliance starts.
But, when the switch is off, the circuit breaks and the current no longer enters the appliance. So the appliance stops working.
This is a simple version of the circuit. But in reality, there are many more components in the circuit.
Circuit with more components
 The electricity from the transformers flows through the wires and reaches the meter outside our house. From the meter, the electricity travels to the main switch in our house, then to the switchboard. When we press the switch of the bulb, the electricity reaches the bulb and the bulb glows.
This process happens in an instant because the electric current or electrical energy travels at a speed close to the speed of light ([latex] 3 \times 10^{8} \frac{m}{s}[/latex]).