A way for functions to be fired after 'scroll' and 'resize' events have been completed, instead of on 'scroll' and 'resize', which fires many times during scrolling. The initial idea was to use this to prevent multiple animations from firing in quick succession, and for animations to wait until the event has been completed. However, I'm sure there are more beneficial uses too. And it's by no means perfect or complete. So feel free to elaborate on this as you please.