title: Javascript variables-- What does it mean when add () after the variable?
body: <p>I just started learning js from <a href="http://eloquentjavascript.net/chapter3.html#p33f5c110" rel="nofollow">EloquentJavascript</a>
  I need 2 answers to help me pass this example:</p>
  
  <pre><code>function makeAddFunction(amount) {
    function add(number) {
      return number + amount;
    }
    return add;
  }
  
  var addTwo = makeAddFunction(2);
  var addFive = makeAddFunction(5);
  show(addTwo(1) + addFive(1));
  </code></pre>
  
  <h2>Question 1:</h2>
  
  <p>Can we just add () after variable meaning to add argument to the function that the variable represent? like addTwo(1) means makeAddFunction(1)?</p>
  
  <h2>Question 2:</h2>
  
  <p>makeAddFunction(2) means amount = 2, then what's the value for number? If I pick a section of the above example,  what will return in the following section?</p>
  
  <pre><code>function makeAddFunction(2) {
    function add(number) {
      return number + 2;
    }
    return add;
  }
  </code></pre>