what is the difference between Automation object model(AOM) and test object model(TOM)?

By using QTP automation object model, we can automate QTP operations.

By using object, methods and properties provided by QTP, we can write programs that can configure QTP operations and settings.

For example, you can create and run an automation program from Microsoft Visual Basic that loads the required add-ins for a test or component, starts QuickTest in visible mode, opens the test, configures settings that correspond to those in the Options, Test Settings, and Record and Run Settings dialog boxes, runs the test, and saves the test.

Test Object Model, is nothing but how QTP identifies the objects in the application.

How to get the class of an object, what mandatory and assistive properties are used during recording the application, how it identifies the objects during run session etc...