title: What are the main differences between R data files?
body: <p>What are the main differences between <code>.RData</code>, <code>.Rda</code> and <code>.Rds</code> files?</p>
  <ul>
  <li>Are there differences in compression, etc.?</li>
  <li>When should each type be used?</li>
  <li>How can one type be converted to another?</li>
  </ul>