You old timers really don't have a grasp of anything in the world. Twenty-five years ago, hell even 15 years ago, tapes were around. I'd say that anyone under 7 years old may not know what they are looking at, not 30, but then 7-year olds are not your typical clients.
Why do old guys always try and make themselves part of a clique by alienating young people? It's pretty sad.
Truth is that even if things are not used nowadays, people still know what they are and what they were used for. And no, not because of wikipedia, but because these things are out there in society, in people's houses, being used by people, and as such the human brain questions everything it sees and that's how the younger generation knows so much. It's old timers that have no idea what modern technology is, that's the only truth. It's always funny when I hear the term "app" being mentioned and I see an old timer's face look all confused and helpless (and that's not even a terribly modern term).