There was a hand from each of her men giving her the "go ahead" squeeze to her knee to unleash the inner swot, "That is a CD which is an acronym for compact disc, they started being mass produced in the early eighties after you went away. The purpose is to store music digitally, and it produces a crisper sound than you can find on vinyl. Now before you say anything, I know you love the crackling, but this is how music is being sold these days, so we thought we’d start by getting you all your favorites, and then mixing in some new artists we thought you’d like! The twins set up a state-of-the-art speaker system in the lounge while we were out yesterday. I wanted to get you a portable player you could wear on your hip and take around with you, but I was kindly reminded that wizarding travel is instantaneous, but it’s ingenious really for muggles who have to take public transit."