From the abstract:
Functional Reactive Programming (FRP) is a simple and elegant way to design and structure interactive code, like games and GUIs. Elm is a young functional language that brings this approach to the web, allowing you to easily create complex interactions.
This talk will fully explain the key concepts of Functional Reactive Programming, building up to live-coding to show these ideas in action. It is pretty easy to integrate Elm into existing JS projects, but the key insights of FRP will help you write better programs in any language.