Server Side Includes (SSI) is a well-known server-side scripting language, used to include the content of one file inside of another file. It is employed typically with online content and it can help to make a static HTML site far more dynamic. If you need to have a daily quote displayed on a variety of pages within your website, for instance, you can make a text file and replace the quote inside it every day. All the pages where this file is incorporated are going to show the updated quote, so you will not need to modify every one of them manually every time. SSI could also be used to include the output of simple functions as opposed to a static file - for instance, the client's IP address, a hit counter or the present date and time. In this way, you may make your website appear far more professional and a lot more attractive to the visitors. Pages that use SSI have a .shtml extension.