Now you will discover how to change between Perspective and Orthographic view:
Press 1, 8, 8, 4, 4 on the Numpad to get a nice angle on the cube.
Press the 5 key on the Numpad.
Press it again.
When you press the 5 key on the Numpad, the 3D View switches between Perspective and Orthographic views as in the previous illustration.
Now it's time to play. Using what you have learned about navigating in the 3D view, experiment by finding different angles to view the scene and shifting between Perspective and Orthographic views and see how they compare. Be sure to try views like top, left, and front, as well as using the 2, 4, 6, and 8 keys to gently rotate the scene. Or you can use the Alt key and your mouse if you like.