To have a closer look at the slides especially when working with diagrams and pictures, 'View -> Zoom' option
can be used. An slide can be zoomin or zoomout with percentage values. The 'fit' option aligns the slide to the powerpoint window. Zooming Slides in Microsoft Powerpoint 2002
In the above example, the slide is zoomed to different sizes like '33%, 50%, 100%' etc.
Thus, zoomin and zoomout can be performed in powerpoint.