A family of Microsoft presentation graphics products that offer tools for creating presentations and adding graphic effects like multimedia objects and special effects with text.
Per slide.
Each slide object can contain a collection of shape objects. Each element of the collection (ie, each shape) will have a unique ID (and in theory a unique name, but that's pretty well broken, so don't count on it).
Likewise a presentation object can contain a collection of slide objects, each with a unique ID.