Motivation
After months working with Flow - the static type checker for JavaScript open-sourced by Facebook - I think it would be beneficial if there's a guide about gotchas, tips or tricks to use Flow correctly and make full use of its advantages.
Honestly, I was looking for such a project to help JavaScript developers master Flow but I found nothing. So I created this project and contribute my personal thinkings to it. If you have any suggestions, please make a PR to improve it.