How does the Notes Work?

Defjeep213:

One thing I didn’t notice in the document that sberman shared, is about where these notes are stored (besides just the local copies): They are a part of many (most) of your various e-mail services—gmail, aol, exchange, whatever.

Going to Settings -> Mail -> Accounts, you’ll see your various accounts, and, in small print, what services you are actively using with each of those accounts.

Clicking on an account will show you what services are available for that account.

Notes is a service that is available on many (most) of those accounts.