title: why we are using HTMLInputElement in typescript?
body: <p>Why we are using:</p>
  
  <pre><code>(document.getElementById("ipv") as HTMLInputElement).value;
  </code></pre>
  
  <p>instead of:</p>
  
  <pre><code>document.getElementById("ipv").value;
  </code></pre>
  
  <p>?</p>