Question about custom field

Custom fields work as name value pairs.

In the custom fields section under “name” input “exp_date”(or something) and under the “value” put “May 13th, 2010″(or diff format).

To retrieve in template file:

<?php
// get the custom field value by this function
$expDate = get_post_meta($post->ID, 'exp_date', $single = true);
// if there is a value input for exp_date
if($expDate !== '') {
?>
// Do something here like echo $expDate;
<?php } ?>

The option to select “exp_date” will now be for each post and wp will remember which value is assigned for each post. If you put nothing, the code will be skipped.

Just a word of caution with how you “structure” the date in your custom field–if you are going to use query_posts to return a sorted list of posts by that custom field you would want to use a date that would be like “2010-04-24”.

Where should I add this code?

Put that in The Loop which is typically a structure that begins with

<?php if (have_posts()) : ?>
<?php while (have_posts()) : the_post(); ?>

and ends with an

endwhile and endif or }