HTML Checking for Large Sites

Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.

Bad character “X” after “<”. Probable cause: Unescaped “<”. Try escaping it as “&lt;”.

The < and > characters are reserved for HTML tags, so if you need to use them as content, they should be escaped as &lt; and &gt; respectively.

For example, to illustrate the mathematical truth that 1 < 2 in HTML, we can write it this way:

<p>1 &lt; 2</p>