[flexcoders] Variable instances behavior in Actionscript

[williamkusumo]

Very stupid question which has been bugging me for a while and just
might be the most basic question in this group.

How does a object instance behave in Actionscript? Say if I have this:

var a:Book = new Book();
var b:Book = a;
var c:Book = b;

So does c actually point to the instance that a and b is pointing to
or is it pointing to b?

And if I do this:

c = null;

Does a and b get nulled too or does it act more like a pointer where
it means c is now pointing to null, a and b still points to the object
instance?

Thanks!