Facebook Like Button is a simple yet powerful way to let your web site visitors to share your content with their friend or like your Facebook page without leaving your site.

The details info of Facebook Like Button can be found at:
http://developers.facebook.com/docs/reference/plugins/like/

Adding a Facebook Like Button using Facebook plug-ins is very easy. However, there are many web sites that are not utilizing the plug-in. They usually put a Facebook icon on their pages and like that icon to their Facebook page. This way cannot provide a streamlined experience for web site visitors.

For example, in our team project, on http://www.basehockey.ca/, we have:

As we can see that buy using the Facebook plug-in, the user experience is greatly improved:

As we can see from the screenshot, visitors can like Comm100’s Facebook page directly and go to Comm100’s Facebook page by clicking “COmm100 on Facebook”.

There are several other formats for Facebook Like Button. You even show how many fans you have, who the latest fan is, or what people are talking.