title: Memory leaks and closures in JavaScript - when and why?
body: <p>You quite often read on the web that using closures is a massive source of memory leaks in JavaScript. Most of the times these articles refer to mixing script code and DOM events, where the script points to the DOM and vice-versa.</p>
  
  <p>I understand that closures can be a problem there.</p>
  
  <p>But what about Node.js? Here, we naturally don't have a DOM - so there is no chance to have memory leaking side effects as in browsers.</p>
  
  <p>What other problems may there be with closures? Can anybody elaborate or point me to a good tutorial on this?</p>
  
  <p><em>Please note that this question explicitly targets Node.js, and not the browser.</em></p>