Put tape over your webcam

[InbetweenDreams]

Webcams have built in microphones. Can people be hearing our every noise i wonder threw the webcam microphone?

Yes...

While I'm not a hacker but given my knowledge I would think it would be easier to find an exploit in the API under windows to access a microphone, because it doesn't have to be a webcam mic, can be any microphone plugged into your computer.

Once you load the driver software for a device, something like a sound card or camera there is a standard API, the API allows programmers to access a wide range of devices with the same code and libraries. Otherwise, programs would be huge to support each manufacturer's wide range of devices... The driver software does translation sort to speak...