As a warning to other toilet paper rolls.

Ooh, I didn’t know about that! But I think I’d be more surprised if it wasn’t real.

Linux is just a kernel. Emacs/Linux is the OS.

Slip them your number on a note on top of cash for your purchase?

This. I used to also keep a notebook with me and jot down the commands I used often. Eventually I learned other ways to jolt my memory and learned to use man. As time went by I used my notebook less and less.

It’s a little hard to iterate and think when you’re adding to a complicated codebase you might not have worked with in several months, or even just a portion of a project that’s seemed stable for a long time. In that scenario, debuggers are able to shorten the getting up to speed process by quite a bit.