Adding Facebook Share to your website is easy. However, you can enhance how the shared item appears on Facebook by configuring how it gets previewed on a user's profile and when a user tries to share it. You do this with a combination of <link> and <meta> tags. Facebook Share passes along the URL of your page to our servers, which in turn looks up certain HTML tags within it. Those tags are used to display a preview of the page. In order to provide this preview, we always look for the title of the page, a summary of the main content and an image. If there's media content on the page, those media files are also important to identify.