Pre-Like / Like Functionality
This feature gives you the ability to hide content from Facebook users who are not fans of your Facebook page. This feature is particularly efficient when you are hosting a competition through your Facebook fan page, and helps establish a campaign that increases your Facebook fans.
After the user has clicked on the "Like" button, they become fans of your Facebook page. Once they are fans, they will be able to access all content on your fan page, such as competitions and free gifts.