Server Side Includes (SSI) is a popular server-side scripting language, used to include the content of one file inside a second file. It is used mainly with online content and it can help make a static HTML website a lot more dynamic. If you'd like to have a daily quote displayed on multiple web pages on your website, for instance, you can make a text file and switch the quote inside it every day. All pages in which this file is included are going to show the updated quote, so you will not need to change every one of them personally every single time. SSI could also be used to contain the output of basic functions instead of a static file - for instance, the client's IP address, a hit counter or perhaps the current time and date. By doing this, you may make your website appear a lot more professional and more appealing to the visitors. Pages that employ SSI get a .shtml extension.