Identify custom objects

How to identify the custom objects in web and client server applications.
Once identified how to decide this custom object maps to this standard object/standard class.
As there are lot of standard classes in tool->object identification->click user defined->mapping dialog box.
Can some one provide list of custom objects we come frequently in web and client server applications.

hai friend,

Will you please let me know what do you mean by custom objects here so that I can help you out.

As per my understanding custom object means list of properties to identify an object
for ex:
WebEdit: It can be identified by name and html tag

If you are looking for some other thing then let me precisely please.

Thanks
Deepa