Much of the value of SPECIFICATION is that it unifies application functionality that may seem quite different. We might need to specify the state of an object for one or more of these three purposes. 1. To validate an object to see if it fulfills some need or is ready for some purpose 2. To select an object from a collection (as in the case of querying for overdue invoices) 3. To specify the creation of a new object to fit some need
