title: Prototype and 'this' context confusion
body: <p>So, I am going thru some old saved code snippets and doing a rote "learning" technique on them etc.. Anyways, I came across some code that I don't remember HOW it worked, so I wanted a refresher.</p>
  
  <p>I have two objects and I want to do a mixin (I know there are other ways, and I have those remembered, BUT this one below is the one I need more explanation).</p>
  
  <pre><code>var MAN = function() {
     this.name = "MAN."
     this.run = function() {
        console.log("I AM RUNNING", this.name, this.age)
     }
     this.walk = function (){
        console.log("I AM WALKING")
     }
    return this
  }
  
  var Billy = function() {
    this.name = "BILLY"
    this.age = 998987
  }
  
  MAN.call(Billy.prototype)// &lt;--- THIS is where I'm having issue
  var d = new Billy()
  console.log(d.run())
  </code></pre>
  
  <p>I understand what is happening in that "call" is setting the "this" context of MAN, to Billy.... BUT, why am I not doing</p>
  
  <pre><code>var d = new MAN()...
  </code></pre>
  
  <p>I am setting the context OF <strong>MAN</strong>, NOT of <strong>Billy</strong>... I am seeing "Billy.prototype" here as being borrowed, NOT modified. How is call doing this.. I figured that MAN is being iterated over and the this context of Billy is assigned to it.</p>