CSS selector class and element order

Question

In a HTML table with class of 'testtable', is there any difference between selecting a element in that table with the following two css selectors?

.testtable td{}

and

td.testtable{}

Answer 1

.testtable td{} selects a td that has a parent with the class testtable, for example:

<table class="testtable">
    <td>I'm selected</td>
</table>

td.testtable{} selects a td that has the class testtable, for example:

<table>
    <td class="testtable">I'm selected</td>
</table>