Given the following example:
<table>
<tr>
<td></td>
<td></td>
<td></td>
</tr>
<tr>
<td></td>
<td></td>
<td></td>
</tr>
</table>
there are a couple of ways to do it
$("table tr td:first-child").each(function() {
//perform actions on all of the first TD elements
});
$("table tr td:not(:first-child)").each(function() {
//perform actions on all of the other TD elements
});
Or
$("table tr td").each(function() {
var td = $(this);
if (td.is(":first-child")) {
//perform actions on all of the first TD elements
}
else {
//perform actions on all of the other TD elements
}
});