You can choose to show or hide various labels and graphical objects inside the Graphic Display window with the Graphic Items toolbar (View | Toolbars | Graphic Items). Hiding some of these objects from time to time may de-clutter the Graphic Display window so that it's easier to perform certain operations.
These are the items you can show or hide:
CAD models
GD&T
Characteristic IDs
Rotation Widget
Feature Labels
Point Info Labels
Feature Control Frame Labels
Dimension Info Labels
Cross Sections
Label IDs
Probe
Machine
Tool Changer
Fixture
Clearance Plane
ClearanceCube
For information on the Graphic Items toolbar, see "Graphic Items Toolbar" in the "Using Toolbars" chapter.