Displaying explanatory text on mouse-over in Powerpoint

To display an explanation of an item when mousing over it in Powerpoint:

1. Add your textbox and type the text.
2. Select the textbox.
3. Right click the textbox.
4. Goto Insert / Hyperlink and click on the Bookmark button.
5. Select your current slide in the current presentation.
6. Click on the Screen Tip button and type in your definition.