Final answer:
The fixed toolbar at the top of the Revit dialog is called the Quick Access Toolbar, which provides convenient access to frequently used commands and tools.
Step-by-step explanation:
The toolbar located at the top of the Revit dialog that is permanent and fixed is known as the Quick Access Toolbar. This toolbar allows users to readily access commonly used commands and tools within Revit. It is customizable and enables users to pin their most frequently used tools for easy access, thus enhancing efficiency and productivity when working on projects in Revit.