title: Does node.js use threads/thread pool internally?
body: <p>I've decided to familiarize myself with node.js and have read a several articles on the subject. What remained unclear to me is if node.js creates new threads and/or schedules tasks on threads from a thread pool when you call  node.js functions.</p>
  
  <p>For example if I call <code>fs.readFile</code> is it executed on a different thread?</p>
  
  <p>If yes, [how] can I write my own function <code>readFileCustomized</code> or <code>doLongOperation</code> to run on a different thread?</p>