I want to add a script code into <head> of single post pages of specific categories. How can I do that?
Step1. You should create another header with your code... Step2: In single .php insert: <?php if ( in_category('3')) { include(TEMPLATEPATH . '/newly-created-header.php'); } else { get_header(); } ?> Of course you will need to change the category id and header name This should work.