A tooltip may refer to any of the following:
1. Alternatively referred to as a balloon, help balloon, or ScreenTip, a Tooltip is a tip given to an object when the mouse cursor is placed over it. Tooltips are helpful for new users because they enable the user to learn about each icon or object by hovering their mouse over them. The picture shows an example of a tooltip in Microsoft Word describing the formatting marks button as showing marks or hiding the marks. Placing your mouse over this picture also give you a tooltip in your browser.
Another example of a balloon is the balloon on the Start button in early versions of Microsoft Windows that shows "Click here to begin".
With a touch screen, you cannot hover your finger over an object, which means tooltips are not available.
2. Balloons and tooltips are also found in Internet browsers as alt text or title text. For example, when hovering your mouse over any of the pictures on this page, you should see a description.