When you start 3D Studio MAX, the main screen contains four equal-sized viewports. The one in the lower right is a perspective view, and the others correspond to the three views used in traditional drafting: top, front, left. By default, the perspective view is Shaded + Highlight. You can choose different views to display from the right-click Viewport menu.
One viewport, marked with a white border, is always active This is where commands and other actions take effect. Only one viewport at a time can be active. Other viewports are set for observation only; unless disabled, they simultaneously track actions taken in the active viewport.
In general, a viewport becomes active as you work in it. You can move an object in one viewport, then drag the same object in another viewport to continue the move.
When you are not in sub-object mode, and the cursor pauses over an object in the viewports, a tooltip appears with the name of that object. Tooltips can be turned on or off on the General page of the Preferences Settings dialog.
You can control many aspects of a viewport with the Right-Click Viewport Menu.