In the lower right is the zoom options.

(1) The first option is largely unknown to many users, partially because it is not needed often. Clicking the percentage number opens the zoom dialog that has presets and ability to manually enter a specific zoom.

(2) The zoom slider was introduced in PPT 2007 and a is a great way to adjust the zoom level. Zoom ranges from 10% to 400%.

(3) Clicking the far right box is the ‘Fit to Screen’ option which I use a lot!

(4) The fourth option is a combination keyboard/mouse feature.
– Hold the CTRL key
– Roll the mouse scroll wheel. Forward = zoom in. Backward = zoom out.

– Troy @ TLC