Are Powerpoint slides an essential part of every presentation?

There has been a lot of hype recently about the fact that PowerPoint celebrates its 25th birthday this year. The popularity of Microsoft's PowerPoint program has led many people to believe that it is not possible to give a presentation without having a slide show be presented on a screen behind the speaker. Strangely PowerPoint continues to be a big source of income for Microsoft, despite the fact that there are now many alternatives to PowerPoint available which are just as good and many are substantially cheaper (e.g. Symphony and OpenOffice are free).

Although most people use slides for their presentations, I notice that the best and most engaging speakers often don't use any.

• I recently give a presentation to the UK Lotus User Group without the benefit of any slides. Although I would not claim it was a brilliant presentation, it certainly was a much more interactive session than if I had been presenting a pre-prepared deck of slides.
  
• At a recent diversity conference within IBM, I noticed that the majority of the speakers simply used a single slide with their name and affiliation. Since the speakers were mainly speaking about their own personal life story and how they had managed to overcome discrimination it is not surprising that they could speak passionately about the subject without having to rely on reading out slides.
  

Thinking about this, I came up with the following observations about when sideshows are both good and bad.

• The slides can serve a useful reminder to the speaker about what they intended to say and/or they can serve a useful reminder to your audience of what you said if your circulate a copy to your audience.


• People often forget that it is possible to put something different on the screen from what is in the notes shown to the presenter. I strongly suggest that speakers should remember this because otherwise the audience will simply read your slides (quicker than you can speak) and tune out from listening to you.
• Many academics report that students read the slides in advance to decide whether or not it is worth their while to attend the lecture. For this reason some lecturers often deliberately leave out key facts from their notes in order to encourage attendance


• If you need to see the slides to remind you what you intended to say, it is a sure sign that you did not do enough preparation.




• The slides can discourage questions because they give the impression that the speaker has a tightly prepared script and does not welcome any interruptions. If you are presenting to a very large audience this might be good, but in most situations it would be better to encourage the audience to enter into a dialog about the topic.


• The slides help remind you whether you are going too fast or slow. Some people aim to spend 3 minutes talking about each slide. While it is bad to be so rigid in your timing, it is perhaps good to have some indication about whether or not you need to speed up or can afford to slow down (keeping in mind the points above that there should only be a loose relationship between what is on your slides and what you say).