Server Side Includes (SSI) is a group of directives that will allow you to incorporate the content of a text file inside an HTML file. In this manner, you're able to add any kind of content to a few different webpages on your site and adjust it by simply editing one text file. You can also incorporate the output of various scripts so that the present date and time, the IP address of the visitor or the attributes of a file show on your site. This shall let you add some dynamic content to static pages, making the site more appealing to your site visitors and creating a more professional appearance. It will likewise be easier to revise this content in comparison with editing every static page one by one. If you wish to use Server Side Includes in your site, the web pages that include the content of any kind of file must be with extension .shtml.