title: Difference between [(ngModel)] and [ngModel] for binding state to property?
body: <p>Here is a template example:</p>
  
  <pre class="lang-html prettyprint-override"><code>&lt;input type="number" class="form-control" [(ngModel)]="overRideRate" formControlName="OverRideRate"&gt;
  
  &lt;input type="number" class="form-control" [ngModel]="overRideRate" formControlName="OverRideRate"&gt;
  </code></pre>
  
  <p>Here both of them do the same thing. Which one is preferred and why?</p>