title: Are there any javascript libraries for interface introduction/tutorials
body: <p>I would like to know if there are any javascript projects which help to give a "tour" 
  within a new web interface.</p>
  
  <p>E.g. when Google changes interfaces in popular apps like gmail or maps you usually have the option, when you visit the first time, to see tipps/hints/videos etc. what you can do where.
  Some Android/iOs Apps do this kind of introduction as well.</p>
  
  <p>I would expect, that you could maybe define some events, that need to be triggered until you get to the next step and other events that trigger notifications/popups of any sort.</p>
  
  <p>I found it hard to google for such functionality. Maybe this doesn't exist and I need to write it from scratch</p>