If your analysis a WordPress category, you will see a word category associated with URL link structure. The order of such a link will be like http://www.domain.com/categoy/catergory name/. These category links look fine in appearance, but it would slightly alter the seo or search engine positions of associated WordPress posts. We can remove the word category from WordPress category URL by .htaccess method or by using plugins. However, using .htaccess it is a little difficult for first time WordPress users. So here we introduce you to plugin Top Level Categories, that can do this without many hassles.
Wordpress 2.8 users can move to plugin installer and search for Top Level Categories. Install the corresponding plugin and activate it from installed plugin page. Now the prefix word category will be removed from the WordPress URL links. This upgrade is not recommended for users with a large number of posts as it might result in few 404 pages. You will not see a drastic improvement search result. However, this would help you to rank better than before.
When you use .htaccess to change this you are effectively creating a redirect, which is not optimal, a much better ways is what is described in this post: