Gather 'round children.
Once upon a time, when a person wanted to have a collection of music, they made something called a mix tape. In order to make a mix tape, a person needed a number of things, including (but not limited to) a cassette, a bunch of vinyl records (REH-cords), and a mysterious collection of electronic funkery known as a stereo, which had spinning things and dials and wires.
A person would put one of the vinyl records on a turntable, put a blank cassette in the cassette player, turn on the turntable, press a record (REE-cord) button, and then--using a number of levers and arms or (heaven help us) one's own trembling hand--place a tiny needle on the revolving vinyl record. The music that had been magically imprinted on the revolving record would transfer onto the blank cassette tape.
Any number of terrible things could go wrong during this delicate process.
There were tiny holes on the top of the cassette tape that are hard to explain, but had to do with whether or not you could record onto the tape. When a person wanted to record over a cassette that they were absolutely sure beyond a shadow of a doubt was filled with obsolete content, they'd cover the holes with Scotch tape (not to be confused with the cassette tape) and that old cassette was ready to roll.
But sometimes, that person who was oh-so-sure of herself wasn't careful about using labels and always putting cassette tapes into their proper cases and she would make a mistake about the content that was on that cassette (usually when it was too late). Sometimes a person would say a lot of very bad words when they realized they'd just recorded over a cassette that was full up with the Pogues and the Band and Roxy Music instead of the Ray Coniff Singers.
Other things concerning the needle, something known as "pitch adjustment," and dial settings could go wrong no matter how hard a person tried to make sure all those things were properly adjusted. As with the over-recording, a person often didn't realize these mistakes until it was too late: they'd go to play their new mix tape only to be met with garbled muck, music coming from just one speaker, or a flat buzz. This was a very bad thing because recording a cassette tape took about a whole day!
Now you children run along and fetch your iPods and earbuds. Go curl up in bed.
What's that you ask? Why did we transfer the music from the revolving disc onto the cassette?
That's a good question. If you're real good, maybe tomorrow night, Auntie Erin will tell you about something called a Walkman.
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