Sliders are used to display a range of different images, any number of images.  Sliders can be adjusted in size.
The display time for sliders can be varied, display from left to right, top to bottom, fade-in/fade-out etc.

‘Overlay Slider’ is just for 2 images, when the mouse is placed over the image it swaps to the second image.

Note: Sliders not only display images, they can work with “Text Boxes”.  You can even have a combination of image/s and text boxes on the one ‘Slide’.