title: Difference between the static and instance sides of classes
body: <p>I am trying to understand interface topic in Typescript 
  when I came across <strong>Class type</strong>, I got this code from <a href="http://www.typescriptlang.org/docs/handbook/interfaces.html" rel="noreferrer">official docs</a></p>
  
  <pre><code>interface ClockConstructor {
      new (hour: number, minute: number);
  }
  
  class Clock implements ClockConstructor {
      currentTime: Date;
      constructor(h: number, m: number) { }
  }
  </code></pre>
  
  <p>I can understand that <code>Clock</code> has no match for the signature  <code>new (hour: number, minute: number);</code> that's why we get an error there.</p>
  
  <p>But in docs the explaination is something which I am unable to understand. It goes in this way :</p>
  
  <blockquote>
    <p>This is because when a class implements an interface, only the instance side of the class is checked. Since the constructor sits in the static side, it is not included in this check.</p>
  </blockquote>
  
  <p>Any explanation would be appreciated.</p>