show programation text in html code example

Example 1: html show html code as text

<pre class="line-numbers">
  <code class="language-css">
    p { color: red }
  </code>
</pre>

Example 2: html show html code as text

<script type="text/html">
<h1>Hello World</h1>

<ul>
    <li>Enjoy this dodgy hack,
    <li>or don't!
</ul>
</script>