How is this IF statement working?

I have the following code which is working, but I don't understand why it works. It is an IF statement, and what happens is if $VAR has a value it displays the DIV, but if it doesn't, it wont display the DIV. I am new to programming, and I would think that the way I have the code, the DIV should not show up if $VAR has a value. Please help me understand. Thanks!

<?php
    if (!empty($VAR)) { ?>
    <div class='543'>
        <H1>Complete.</h1>
    </div>
<?php } ?>