Put the B side on

Grandma phoned tonight she told daddy that Uncle Peter was winding her up so daddy did come to her defence but also had a laugh about it. Grandma CD player is broken so she asked Uncle Peter to put her new CD on via her laptop which he did. As it was a single CD when he came back she asked him to turn it over for the b side. Daddy did say you can get double sided CD. But he had to explain to me what the b side was. Apparently before CD you had records and the main song was the a side and any others the b side. So poor grandma got confused