Resolution is the "resolution" value a user selects when marking an incident as resolved, and describes how the incident was resolved e.g. "Fixed", "Wont Fix", "Can not Reproduce" etc.
Values are determined by the options available on the Resolution picklist in Enterprise Tester, for example:
Resolution = Fixed
To find all incidents within a project with the incident resolution of Won't fix:
Project = "TEST" AND Resolution = "Won't Fix"
=, IN, !=, NOT IN, IS, IS NOT