How do you know?  How can you be sure you reach every slide simply by pressing space?<p>What about on my tablet, which doesn&#x27;t have a space bar?<p>Edit: These are genuine questions, and I am <i>deeply</i> frustrated that it&#x27;s being downvoted without any discussion.  People are claiming that hitting the space bar takes you linearly through the entire presentation.  <i>How do you know you reach every slide like that?</i><p>Really, seriously, how do you know?<p>As far as I&#x27;m concerned the navigation is opaque - if I hit space, I don&#x27;t know that I&#x27;ll reach every slide.<p><i>How do you know ?!?</i><p>I suspect that people are enamoured with the attractiveness of the presentation - it&#x27;s cool, it&#x27;s slick, it&#x27;s gorgeous, it&#x27;s wonderful - and when I question its usability or discoverability, people are downvoting because they have no answer, and just get pissed off at being questioned.<p>Do you actually have an answer?  If so, tell me.