Looking for a similar answer and arrived here, still without clues. Finally found a little more explanation (and examples) from an article here:
[To see links please register here]
I am not the original author, so I can only quote some texts:
> What are Drupal Behaviors?
>
> In short, Drupal.behaviors is a more modular and better way to
> implement jQuery.ready. Unlike jQuery.ready which only runs once when
> the DOM is ready for manipulation, Drupal.behaviors can be ran
> multiple times during page execution. Even better, they can be ran
> whenever new DOM elements are inserted into the document (i.e. AJAX
> driven content).
>
> Drupal.behaviors can also override or even extend an existing
> behavior. So for instance, if a module behavior adds a bounce effect
> on all links, another module could replace that behavior with a
> different bounce effect.
>
> Another added bonus of Drupal.behaviors (starting in Drupal 7), is the
> ability to use the drupal_add_js (PHP) or Drupal.settings.modulename
> (JS) and pass settings as a second parameter (the first being the
> context) to the behavior.