What exactly $event object do in Angular 2?
<p>I am bit confused what exactly <code>$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>