What do you mean you've never seen a cassette?!
I used to take my Walkman everywhere! I would also carry no less than 5 cassette tapes on me at any given time.
I also had mental markers for each cassette, so that I could stop a song at a certain point...flip the tape over...and hear a different song from the beginning.
I always had cheap Walkman's though and eventually they'd eat my cassette.
Heck, I remember when I got my Discman. I thought I was so cool. (I wasn't).
Kids today have no idea how easy they have it.