How can 'Data Abstraction' be made useful in the real world? Explain with an example.

Electrical switchboard is an example of Data Abstraction in real world. To switch on or off a particular light or fan, we press the required switch to on or off position. We don't worry about the things like how the the circuit is affected by the switch, what is the internal wiring, etc. Switchboard hides all such background details from us and provides a very simple way to operate the lights, fans and other electrical appliances.