As stated previously, the . (dot) character is used to delineate the Object name and the contained property/ method or event. An Object can also contain 'child' objects. Again, the . (dot) character is used to delineate between the Object and its child Object.
Assume an Object named obj1 has a property _x. That property can be accessed as obj1._x
If obj1 is a child object of obj2, then the reference to obj1._x is only valid from within obj2.
To access the same property from outside of obj2, the full name is required. This name would be obj2.obj1._x
Because of the hierarchical nature of Object names, the following synonyms _root, _parent and this are implemented to represent (in order) the top-most object (always the main Movie), the immediate parent and the current Object. These synonyms are described in further detail in the Scripting Reference Manual.