In order to use SSI (Server Side Includes) in you web pages, you must first make sure that it has been enabled for your website. E Street, by default, does not automatically enable SSIs. You can request we turn it on for you by sending a message to ‘firstname.lastname@example.org’. This service is not available on all servers.
To help understand what SSI’s can do, we have an online tutorial that you can read at: