In previous posts in the series we discussed namespaces, an introduction to the new Spark components architecture and the new mxml tags introduced with Flex 4.
This post is all about data binding, and two-way data binding new to Flex 4 specifically.

Basically, data binding is like taking a piece of string and tying each end to an object, so that when the data in one object is modified, the modified data also applies to the other object. The benefits are obvious – an easy way to pass data between different layers of the application or an easy way to catch an event with a single handler and have that handler update more than one object are a few examples.