In addition to OriginalGriff's answer about encoding, have a look at the
pre element[
^] in HTML, which allows you to write code as it is. So, for example (like this example on CodeProject), you can write this
<pre>
<p>This is a paragraph.</p>
</pre>
It will be rendered as,
<p>This is a paragraph.</p>
It will maintain the tags, and they won't be rendered by the browser.