Looking through the wordpress forums I saw a large number of people wanting to know how to remove ‘category base’ from permalinks. For example http://bloggerholic.com/category/wordpress/ 

I found the solution and it’s easy! This is only for Wordpress 2.0+
All you need to do is the following:

1. Go to your wp-includes folder.
2. find the template file called “category-template.php” and open the file in any text editor.
3. Find the follwing line $catlink = $wp_rewrite->get_category_permastruct();
   You will see this code two lines below function get_category_link($category_id) {
4. Below it add the following line $catlink = str_replace(’/category’, ”, $catlink);
   NOTE:
   Due to the font the code has changed, Please make a note to change the curly quotes into standard text quotes.
5. Save the file and upload “category-template.php” in wp_includes folder.

Update: For those using wordpress version 2.61 and 2.62 the above will not work so you will need to do the following:

1. Go to your wp-includes folder.
2. find the template file called “category-template.php” and open the file in any text editor.
3. In this file find the following function, function get_category_link($category_id) {
4. Find the following line inside this function  $catlink = get_option(’home’) . user_trailingslashit($catlink, ‘category’);
5. Below it add the following line $catlink = str_replace(’/category’, ”, $catlink);
6. Save the file and upload “category-template.php” in wp_includes folder.

That’s it your done!

NOTE: Make sure you don’t name your page name the same as category name.

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