Action buttons are built-in button shapes that you can add to your presentation and then assign an action to occur upon the click of a mouse or when someone ‘mouses over’ the button.  I would not recommend the ‘mouse over’ method.

When you deliver your presentation, you can click an action button to:

• Go to the next slide, the previous slide, the first slide, the last slide, the most recent slide viewed, a specific slide number that you specify. a different PowerPoint presentation, or a Web page
• Run a program
• Run a macro
• Play a sound

I often place an Action Button on a ‘hidden’ slide.  If I need to go to the hidden slide during the presentation, then I can click the Action Button to take me back to the slide I had been on.  The setting used is “Hyperlink to:  Last Slide Viewed.”  I always place an Action Buttons on the lower right corner of the slide and make it as small as possible, changing the color of the button so it blends in with the slide background.

PowerPoint 2000 – 2003

Insert an action button on a single slide

1. Select the slide you want to place a button on.
2. On the Slide Show menu, point to Action Buttons, and then select the button you want— for example, Home, Back or Previous, Forward or Next, Beginning, End, or Return.
3. Click the slide.
4. Make sure that Hyperlink to is selected. Click OK to accept the proposed hyperlink in the Hyperlink to list, or click the arrow and select the link you want.

PowerPoint 2007

Add an action button and assign an action

1. On the Insert tab, in the Illustrations group, click Shapes, and then under Action Buttons, click the button that you want to add.
2. Click a location on the slide, and then drag to draw the shape for the button.
3. In the Action Settings dialog box, do one of the following:
   ►  To choose the behavior of the action button when you click it in Slide Show view, click the Mouse Click tab.
   ►   To choose the behavior of the action button when you move the pointer over it in Slide Show view, click the Mouse Over tab.  (I do not recommend this method!)
4. To choose the action that will take place when you click or move the pointer over the action button, do one of the following:
   ►  To use the shape without a corresponding action, click None.
   ►  To create a hyperlink, click Hyperlink to, and then select the destination (for example, the next slide, the previous slide, the last slide, or another PowerPoint presentation) that you want the hyperlink action to go to.NOTE:  To link to a file created by another program, such as a Microsoft Word or Excel file, in the Hyperlink to list, click Other File.►  To run a program, click Run program, click Browse, and then locate the program that you want to run.
   ►  If you want the shape that you chose as an action button to perform an action, click Object action, and then select the action that you want it to perform.
   ►  To play a sound, select the Play sound check box, and then select the sound that you want to play.
5. Click OK.