Some background: We know through research at The Speech Improvement Company that the most effective speakers are able to synchronize their visual aid support so your listeners won’t see the slides until you say it.
In 2001, Apple released Keynote with a feature whereby the speaker could see the upcoming slide before advancing to it and thereby putting in on the big screen for all to see. This was huge. At the time, PowerPoint had a similar feature, but it would only work if you had a desktop computer with 2 monitor cards and a projector, all connected to each other in a specific way.
Keynote was way ahead of its time. Apple reached out to The Speech Improvement Company and asked if we would endorse the software. We don’t normally do endorsements, but this particular feature was very significant. We had not seen anything like it since the invention of the teleprompter. Today, PowerPoint for both Mac and Windows has this functionality.