If you squeeze and review all the PPTs, you would find them a sum-total of textual matter and visual contents. In the age of decreasing attention-span, words are getting diminished from slides and images are getting increasingly relevant.
But to prepare a PPT on the base of visual contents, you must keep away from using inappropriate images, videos or animations. Excessive use of visuals may defeat your purpose. An image or visual must send out the message by itself and textual matter just has to be supporting it.