Ah yes, I forgot that you're a whippersnapper.
Miniature Led Zeppelin Frisbee's , we used to use em in the old days,and even harder to explain would be 8tracks !
What do you mean what are CD's, you have a 91 Honda you know what CD's are. You need to experience car's with an AM radio then you can ask what are CD's.... This is worse than trying to explain to this Mexican gentlemen that used to work for me,he asked me one day "What is this patience? So I explained it to him,how sometimes in life you have to wait on some things, then he said what is this patients at the hospital" and I gave up on him to....