These are mnemonic devices, memory jogs. And Christopher Stevens has compiled a bunch of them in his small book, "Thirty Days Has September." For example, if you're ever called on to name the main ...

Mnemonic devices are memory aids that help you remember a specific thing. They can be acronyms, sentences, rhymes, or any other device that calls the things you’re trying to remember to mind.

"Thirty days hath September" is so last year. Check out these other clever, helpful mnemonic devices to help you remember all sorts of handy little facts.