title: What exactly $event object do in Angular 2?
body: <p>I am bit confused what exactly <code>$event</code> doing here and what is the difference between this two examples </p>
  
  <pre><code>&lt;button (click)="clicked($event)"&gt;&lt;/button&gt;
  
  @Component(...)
  class MyComponent {
    clicked(event) {
      event.preventDefault();
    }
  }
  </code></pre>
  
  <p>and</p>
  
  <pre><code>&lt;button (click)="clicked()"&gt;Click&lt;/button&gt;
  
  
  
   @Component(...)
      class MyComponent {
        clicked(event) {
        }
      }
  </code></pre>