title: trying to understand the implementation of the of() function in typescript/angular?
body: <p>What is the <code>of()</code> function in TypeScript/Angular? </p>
  
  <p>For example, <a href="https://angular.io/tutorial/toh-pt5" rel="nofollow noreferrer">https://angular.io/tutorial/toh-pt5</a> has a reference to: return of(HEROES);</p>
  
  <p>I found the reference to the <a href="https://angular.io/guide/observables" rel="nofollow noreferrer">Observable <code>of()</code> function</a>: </p>
  
  <p>In the sample TOH code <em>url</em> I provided at the first <em>url</em>, the <code>of()</code> function is used independently as opposed to being used with explicit dot notation off an Observable object.</p>
  
  <p>Does the Angular component at the first <em>url</em> I provided maintain some type of implicit component-scoped Observable reference which eliminates the need to call the of() function explicitly via dot notation off of the Observable object? The Observable documentation states:</p>
  
  <blockquote>
    <p>Observable.of(...items)—Returns an Observable instance that
    synchronously delivers the values provided as arguments.</p>
  </blockquote>
  
  <p><strong>TOH</strong> is generally the baseline reference model to use for ng development.  Is <code>Observable.of()</code> generally considered the default way to return data in ng6?  When was the <code>of()</code> function introduced.  I don't remember seeing it before ng6?</p>