title: Using emit vs calling a signal as if it's a regular function in Qt
body: <p>Let's say I have this signal:</p>
  
  <pre><code>signals:
      void progressNotification(int progress);
  </code></pre>
  
  <p>I only recently learned about the emit keyword in Qt. Until now, I used to execute signals by just calling them like a regular function. So instead of:</p>
  
  <pre><code>emit progressNotification(1000 * seconds);
  </code></pre>
  
  <p>I would write:</p>
  
  <pre><code>progressNotification(1000 * seconds);
  </code></pre>
  
  <p>Calling them like that seemed to work, and all the connected slots would execute, so does using the emit keyword cause a different behaviour, or is it just syntactic sugar?</p>