To create sound
Electricty is sent to your headphone to vibrate the coil of the speaker that will reproduce the sound from yor cellphone or computer
they were different,what do you want to know is what you want to think,while what do you want to learn is what you expected. example of what do you want to know: i want to know the kinds of clouds . examples of what do you want to learn: i want to learn about the outer space.
answer: what kind of
explanation: please put the full question..