Recording slides is almost like delivering a presentation that you cannot deliver in person! Let’s imagine that you cannot deliver your slides in person. What you would then want to do is to deliver your presentation in front of your computer, almost as if you had a live audience present — all this while, your narrations are being recorded. Even the time you spend on each slide is recorded along with the time taken for each animation to play. In PowerPoint 2011, as far as interface is considered, there is no difference between the options available for rehearsing slides and for recording a slide show. The only difference is that while recording a slide show, along with the time spent on each slide, your narrations are also being recorded through the connected microphone.