title: What is the purpose of CRX file?
body: <p>Chrome Store does not accept <code>CRX</code> file but simple <code>ZIP</code> file.</p>
  
  <p>So I am confused why the <code>CRX</code> files exist? Also extracting the <code>ZIP</code> file and loading it unpacked option is still an option.</p>
  
  <p>As far as I know Chrome does not allow extension installation other than Chrome Store.</p>
  
  <p>So what is the purpose of the <code>CRX</code> file?</p>