Time for action — rotating the scene in 3D View
When modeling or animating, you frequently want to see differing angles of what you are working on. Rotating your view is often the best way to do this, Try it:
Move the cursor over the cube in the 3D View. Press the middle mouse button (MMB) and move the mouse left and right.
Now try it again, start with the cursor near the center of the screen, and move the cursor up and down.
What just happened?
That isn't too difficult. Pressing the middle mouse button (MMB) and moving the mouse revolves your view around the origin.