When you use the View Selector to modify a model's orientation, it appears with the current model orientation, rather than changing the model orientation.
This makes it easier to change to the desired view orientation. In addition, you can see a preview by moving the pointer over a View Selector plane.
To launch the View Selector, press the Ctrl + Spacebar or click View Selector 
in the View Orientation flyout menu on the Heads-up View toolbar.
As you move the pointer over different planes, the preview window updates. If a view is a standard view, the view name appears in the upper left corner of the preview window.
Planes that are obscured because they are in the back of the model are exploded away from the center of the View Selector to make them easier to select without rotating the model.
The following image shows the right pane selected and the bottom, left, and back panes exploded.
If you rotate the view using the middle mouse button, the positions of the planes update dynamically so you can still select obscured planes.