ul>
<li><p><em>Directive inter-communication:</em> All directives share the same instance of the attributes
object which allows the directives to use the attributes object as inter directive
communication.</p>
</li>
<li><p><em>Supports interpolation:</em> Interpolation attributes are assigned to the attribute object
allowing other directives to read the interpolated value.</p>
</li>
<li><p><em>Observing interpolated attributes:</em> Use <code>$observe</code> to observe the value changes of attributes
that c