When you speak, the microphone picks up your voice, and your computer then converts this analogue information into a digital stream.This stream is chopped up into packets of data. It’s these packets that then head out to travel on the vast highway that is the internet. If those packets arrive quickly, and in the right sequence, then you’ll have a great quality call. (The same in the reverse direction, the voice of the person you are speaking to, needs to reach you too).