title: How to do Aggregation in Node js
body: <p>I am currently finding out ways to do Aggregation in Node js. I have tried to do $lts, $gte and others but im wondering if these are all categorized as aggregation or not. If not, can you please enlighten me a little. Below is what i have. Can i have an example of how to do an aggregation of $sum or $average.</p>
  
  <p>$gte</p>
  
  <pre><code>db.contact.find("machine_unit" : {$gte:5}}, function(err,meibanlist){
    if (err || !meibanlist ) console.log("Record is not found");
  else meibanlist.forEach (function(machine_unit){
  console.log(machine_unit);
  });
  });
  </code></pre>