Have you ever wanted to exclude a particular category from a section of your blog without using a plugin?
For example, because there is already a separate list of videos on the homepage at RosalindGardner.com, I didn't want the videos to show up again in the “Most recent entry posted” featured at the top of the page.
So, to eliminate the Videos category from that section, I first look go to Manage > Categories in my WordPress Administration panel and look for the category ID, which turns out to be #10.
I open the home.php template (you might be using index.php) and add cat=-10 to the code for the most recent post as follows:
< ?php $recent = new WP_Query("showposts=1&cat=-10"); while($recent->have_posts()) : $recent->the_post();?>
Note the minus sign in front of the category number.
If you want to eliminate more than one category from the display, simply separate each category ID number with a comma, such as: &cat=-10,-22 .[tags]blog, wordpress, category, exclusions[/tags]