Explain the concept of 'Rehearse Timings'.

Rehearse Timings feature helps us in finding out the time we would need to present a slide show. This option makes sure that our presentation fits within the certain time frame. We can set a varying time for slides to be displayed before changing to the next slide.

It works in the following way:

1. Practice Run — When we choose the 'Rehearse Timings' option, PowerPoint starts a practice run of our presentation. As we advance through the slides, a timer records the time spent on each.
2. Timing Adjustment — After completing the practice run, PowerPoint provides the option to review and adjust the timing for each slide. This feature is especially useful for ensuring that our presentation fits within a designated time frame.
3. Automatic Slide Advancement — The timings we set during the rehearsal will be used to automatically advance the slides during the actual presentation. This ensures a smooth and well-timed delivery.
4. Speaker Notes — 'Rehearse Timings' also allows us to add or edit speaker notes for each slide, helping us remember key points or cues during the presentation.