Adding Transitions To Your PowerPoint Presentation
In Microsoft PowerPoint, slide transitions are motion effects that occur in Slide Show view when you move from one slide to the next during a presentation. You can control the speed, add sound, and even customize the properties of transition effects. To add a transition first of all select a slide in the left hand panel that contains the Slides and Outline tabs (I'd keep it simple and work in the Slides tab). The transition will occur immediately before the selected slide is displayed. Click Transitions > Transition To This Slide, and then click on the transition you want to use. If you want to see a larger selection of transitions, click on the more button (the down arrow at the bottom right of the group.
When you hover over a thumbnail image of a transition, you can see a live preview of it applied to your slide. When you move the cursor away, the preview is removed.
If, after having applied a transition to the selected slide, you decide that you want the transition applied to all slides, click on the Apply To All button in the Timing Group on the same tab.