When you turn a light switch off, the electricity does not completely stop flowing in the circuit. When you flip the switch, you are interrupting the flow of electricity through the circuit, which stops the current from reaching the light fixture. However, there may still be some small amount of electricity flowing through the circuit due to factors like electrical leakage or residual capacitance.
In most modern homes, the light switches are connected in what is called a "single-pole" configuration. When you turn off the switch, it opens the circuit and breaks the connection between the power source and the light fixture. This interruption prevents the current from reaching the light and illuminating it.
It's important to note that even when the light switch is off, the electrical wiring behind the switch and throughout the house may still carry a small amount of voltage. This voltage is typically not sufficient to power the light or pose a danger, but it's a good practice to exercise caution when working with electrical systems and assume there is always some residual electrical energy present.