HTML Guide for space

An href attribute on an a element contains an invalid URL that has space characters in the domain.

The domain in a URL cannot contain space characters, for example the following are invalid:

<a href="http://my domain.com">link</a>
<a href="http://my%20domain.com">link</a>

Attributes in HTML elements need to be separated by space, in this example the first line is invalid and the second one is valid:

<a href="page.php"class="big">link</a>

<a href="page.php" class="big">link</a>