Spotlight Slideshow cycles through Spotlight's live connections. For each connection the current page is displayed. The time of the display is configurable.
To start the Slideshow, select View | Slideshow. A tick is added to the slideshow menu item.
To stop the Slideshow, click again View | Slideshow. The tick against the slideshow menu item is removed.
Dependent on how the Slideshow is configured
You may configure the Slideshow to begin automatically when Spotlight is not actively in use.
You may configure the Slideshow to end when you mouse over or click in the Spotlight application or click 'x' on the Spotlight toolbar.
For information on how to configure the Spotlight Slideshow, see Slideshow.