ElementControllers are really basic means of binding models with DOM and back and handling management of Views (different fragments of HTML inside the element being controlled) and interstitial states of those views. They can't handle complex relationships, and they don't have a whole templating solution wound up in them either. They don't infinitely shield your code in abstractions, but they keep it fairly clear and decoupled and they are really lightweight.
###Creating a ElementController
You create a ElementController with an element...
var controller = new ElementController(document.body);