While I was in college I met someone else who was going to night school. She was taking computer classes. It was not clear exactly how we got onto the subject but we were speaking about binary numbers. She said that they were talking about this in her class, perhaps I was being a jerk but I asked for a bit more detail.
She said, you know that binary is base two it is about ones and twos. The words had just barely cleared her mouth when she realized what she said. She then corrected herself to mean that binary is zeros and ones – just a second too late.