The Fast Forward button on a cassette recorder is often marked simply “F.F.” for Fast Forward. I used to think that was the button you pressed to make it go “F-F-F-F-F-F” (which it is, of course, but that’s not what it means!).
A childhood belief about technology

others believed things like this
- I thought that when you pressed the hazzard button in the car, the dukes of hazzard would come and save you.— smfd26
- I used to believe that the exhaust fumes coming from a car were actually what pushed it forward like a rocket — rocket car
- i believed that little men sat in the back of vending machines and pushed the sweets forward.— rachael
- I used to believe that good and expensive joggers would make me run fast.— Kats
- I used to believe that inside each volcano there was a guy who'd press a button to make it erupt.— Jim, UK
- I used to believe that if I ran fast enough I could outrun the rain. — Yosa