Oh right. "Um.. it's a.. shit, you don't even know what a computer is. Okay so muggles have these.. mechanical devices.. computers. They're all kind of connected.. through the phone. um.. through this thing called the internet. So.. wait.." she reached in her pocket and pulled out the messaging thing she'd been talking to Severus on before.
"This is a mini version. How you're connected to everyone and can talk to them? Through this. And basically email is .. someone sending you a letter through this. It's instant, no waiting for owl's to come and crap on your lawn," she explained.