What is an Object Model?
the physical layout of objects in memory. E.g. the the COM Object Model, the JVM Object Model.
the nature of objects in a programming language (including everything objects inherit from Object). E.g. the Java Object Model or the Smalltalk Object Model.
a kind of diagram, or an incarnation of that kind of diagram. E.g. the Unified Modeling Language Object Model diagram or the Object Model of an application domain.
a specific configuration of objects at runtime. E.g. if you program in Java Script you have different Object Model-s in Netscape Navigator and Internet Explorer.
The OMT methodology uses the term "object model" to refer the class diagrams (and instance diagrams) used to describe part or all of a system.
Object Model is contrasted with Object Architecture.
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