<p>My good friend, Wikipedia, <a href="http://en.wikipedia.org/wiki/Language_binding" rel="noreferrer">didn't give me a very good response</a> to that question. So:</p>

<ul>
<li>What are language bindings?</li>
<li>How do they work?</li>
</ul>

<p>Specifically accessing functions from code written in language X of a library written in language Y.</p>

In Flex (Actionscript 3).
Source
A data binding copies the value of a property in one object to a property in another object. You can bind the properties of following objects: Flex components, Flex data models, and Flex data services.
The object property that provides the data is known as the source property. The object property that receives the data is known as the destination property.
The following example binds the text property of a TextInput component (the source property) to the text property of a Label component (the destination property) so that text entered in the TextInput component is displayed by the Label component:
```
```
<mx:TextInput id="LNameInput"></mx:TextInput>
...
<mx:Label text="{LNameInput.text}"></mx:Label>
```
```
Data binding is usually a simple way to bind a model to user interface components. For example, you have a class with a FirstName property. In flex you could easily bind that property to a textbox by setting the value of the textbox to {Object.FirstName}. Then, every time that FirstName property changes, the textbox will be updated without requiring you to write any code to monitor that property for changes.
Hope that helps.
Matt