Are Apple Event Demos done in real time? So when there's an Apple Event, and someone does a demo of how Siri works or play a game, etc; Are those done on real time or were they prerecorded? (Just a PPT presentation)
Most demos are done real-time from the console they have off to the side of the screen.  The presentation, and often the code displays, are done with Keynote (not Powerpoint). 

Of course, sometimes demos are actually pre-recorded and this was often done when Jobs couldn't get the real demo to work correctly due to network or other issues.