Server Side Includes (SSI) is a well-known server-side scripting language, which is used to add the content of one file inside of a second file. It's employed principally with online content and it will make a static HTML site more dynamic. If you want to have a daily quote displayed on numerous web pages on your website, as an example, you can create a text file and replace the quote in it every single day. All the web pages in which this file is included are going to show the updated quote, so you'll not have to update them personally each time. SSI could also be used to incorporate the output of basic functions as opposed to a static file - for example, the client's IP address, a hit counter or even the current time and date. By doing this, you can make your internet site appear much more professional and much more appealing to the site visitors. Web pages that implement SSI get a .shtml extension.