title: what is .netrwhist?
body: <p>When I edit files in my <code>~/.vim</code>, the <code>.netrwhist</code> file would mysteriously be changed, too.</p>
  
  <p>It's content:</p>
  
  <pre><code>let g:netrw_dirhistmax  =10
  let g:netrw_dirhist_cnt =6
  ...and so on...
  </code></pre>
  
  <p>What does this file do? Is it important?</p>