Domain Verification is the process of telling Facebook that you own the website. You just need to enter the code to your website and Facebook will use that to verify. Once it’s verified, you can associate your Facebook page with your verified domain so that Facebook knows it’s okay for that page to edit link previews from that website.
With this plugin, you can do that in just a few clicks without worrying about the code. Just copy and paste the code after installing the plugin and you’re good to go.
Here's how you can start using Facebook Domain Verification: