Message model object identification
Objects in a message model (elements, attributes, types, groups) are identified by their name only.
This means that no two objects in the same scope can have the same name. Name clashes can be avoided more easily if global objects are used only when necessary. Local objects are not visible outside of the scope of their parent object, so their names can be reused without causing a name clash.
For details about XML Schema, see XML Schema Part 0: Primer on the World Wide Web Consortium (W3C) website.