title: How to save a Docker container state
body: <p>I'm trying to learn the ins and outs of Docker, and I'm confused by the prospect of saving an image. </p>
  
  <p>I ran the basic Ubuntu image, installed Anaconda Python and a few other things...so now what's the best way to save my progress? Save, commit, export? </p>
  
  <p>None of these seem to work the same way as VirtualBox, which presents an obvious save-state file for your virtual machine.</p>