Answer: as a medium meant to be used in conjunction with someone speaking.
Step-by-step explanation:
Presentation slides are meant to augment what the person presenting is saying. They are to provide proof as well as a visual depiction of the words of the presenter so that the audience can understand the presentation better.
For instance, a person giving a presentation on the earrings potential of a business will use charts and tables to show the expected increase. The charts and tables will help show the point that the person is trying to make so that the audience understands.