The YUI provides a unified event model that works across all A-grade browsers. It also introduces an interface that allows you to create your own custom events. These are important enhancements in several ways.
Firstly, you can save yourself a lot of code as the event handlers can be attached to almost any element in a consistent way, regardless of peculiarities in their inner workings. Handlers can even be attached to multiple elements with ease or multiple handlers can be attached to a single element. A word of caution: if a browser does not signal a particular event, or the Event Utility cannot guess it from other clues, the event will simply not be fired. It is a good idea to check PPK's Quirksmode site, mentioned previously; if the Event Utility does not fire an event you expect, it might simply be because the browser itself doesn't.
The event
object and how it is accessed has also been refined so that it can be obtained in the same way regardless of the browser to...