title: How to choose which type of NoSQL to use
body: <p>There is a great list of various NoSQL database platforms at <a href="http://nosql-database.org" rel="noreferrer">http://nosql-database.org</a>.  It categorizes each as a "wide column store", "document store", "key-value store", or "graph store".  What I'm not finding is guidance on how to choose which of those 3 categories is most appropriate for a given problem.  </p>
  
  <p>What are the pros/cons or strengths/weaknesses of each type?<br>
  Which classes of problems is each type best suited for?</p>
  
  <p>To be clear, I'm asking about distinctions between these 3 types of NoSQL systems and <em>not</em> specific implementations of them.</p>