You may want to have the Facebook like / recommend button on every page of your website. The standard code works great unless some of your pages are secure, using the https:// protocol. Ecommerce websites are the most common example.
This is an easy fix for domains, such as Facebook that support SSL. To avoid browsers SSL warnings that create high anxiety for your website visitors, don’t specify the transport protocol.
In plain English: instead of using http:// or https:// in the code that Facebook gives you, use // instead.