Glyphicon anchoring and variable issue

1. It's just "text"-element. You can put it inside whatever you want.

Code:

<a href="#">
    <span class="glyphicon glyphicon-asterisk"></span>
</a>

echo anchor('#', '<span class="glyphicon glyphicon-asterisk"></span>');

2. No one can answer that question for you, as you haven't provided any source code. But as the error message says; Your variable $video aren't set. So when it tries to check/validate it with ==. It won't find the source of $video and give that exact error message.