overview mode documentation

diff --cc README.md
index fd58c718860d544c921b86a76bc340cdd673d4fc,64579692cd3e04d286fe66115dea0c20a537ed6a..4cb15eb53ec8c7a0486aa316b00075c3e4ba8cef
--- 1/README.md
--- 2/README.md
+++ b/README.md
@@@ -206,6 -203,11 +206,11 @@@ The default fragment style is to start 
  </section>
  ```
  
 -Just press "Esc" key to toggle on and off the overview mode. While you're in this mode, you still can navigate between slides,
+ ### Overview mode
+ 
++Press "Esc" key to toggle the overview mode on and off. While you're in this mode, you can still navigate between slides,
+ as if you were at 1,000 feet above your presentation.
+ 
  ### Fragment events
  
  When a slide fragment is either shown or hidden reveal.js will dispatch an event.