title: Difference between [ngClass] vs [class] binding
body: <p>What is the difference in Angular 2 between the following snippets:</p>
  <pre class="lang-html prettyprint-override"><code>&lt;div [class.extra-sparkle]=&quot;isDelightful&quot;&gt;
  &lt;div [ngClass]=&quot;{'extra-sparkle': isDelightful}&quot;&gt;
  </code></pre>