Drag the mouse up/down to rotate the ColorCube.
Use the "X", "Y" or "Z" key for changing the axis of rotation. The "A" key changes the rotation mode to absolute: rotations will be performed considering the virtual world axis system.
The "R" key changes the rotation mode to relative: rotations will be performed considering the object's local coordinate system.
Trying to navigate while holding down the mouse button will lead to strange effects.