Going back to beautiful days!

What comes in your mind reading the title? School days or those love days or something else! For many of us, those beautiful days were the childhood days too. Remembering those days, what is that one incident which is like oh shit! How stupid i was, to think like that. Like everyone, I too had that incident, have you ever seen written on the back of trucks, tractors or even buses, ' Use dipper at night'. From the time I started reading to the age of 10 or 11 years, I everytime read it ' Use diaper at night'. And seriously I was embarassed to ask someone that why that is written because i thought that's a good habit and everyone must know about it and if I ask, they will make fun of me. So one day when I again read it, I read it loudly so that if I am prouncing it wrong, someone will correct me. And that only happened, my brother told me it's not diaper, it's dipper and when it is used. So that was my stupid thing, what's your's?