A Conversion Funnel is the path that a visitor takes from point A to Point B in your website. If you are already using web analytics and tracking software on your site, you should be able to easily find out what the most common paths are that visitors take while visiting your site.
Funnel tracking is one of the keys to successfully optimizing your conversion rates. If you don’t yet have some sort of tracking installed on your site it is very easy, and free, to get set up with Google Analytics.