A live examples of deferreds?

I am trying to understand how to properly use them with ajax. What I want to do is display an animated image while an ajax function is performing an operation and then remove the image once the request processes, and also display the results. I am being vague but I want to know how exact I would handle a process like that? Can anyone possibly show a live example or some kind of tutorial that shows how to exactly do something like this? For example… someone puts in their login details and while I validate their login I remove the form and show them the image. Once it’s done I say congrats and redirect them. Now I know how to handle everything in terms of animations and what not, just not sure how to make it all work properly with jQuery.

Thanks in advance!