There are two types of Master Slides in PowerPoint. The Title Master and the Slide Master. Each has its own specific purpose and will help the user customize certain elements to ensure consistency in terms of design, layout, and interactivity.

The Title Master is used to customize elements such as animation, font, background, etc. for slides that follow the Title Master. Thus, if a presentation has three different Title slides, all three will follow the Title Master (unless the individual made changes within the slide itself).

The Slide Master is used to keep body slides consistent in terms of animation, font style, background, etc. Again, unless the individual edited particular slides, all the slides that follow the Slide Master will have the same appearance and interactivity.

To edit or view the Master slides, go to View in the menu bar. Then, go to Master and select either the Slide Master or Title Master. You may not be able to use the Title Master (it may appear greyed out) until you apply a design template.