Server Side Includes (SSI) is a simple server-side language, which allows you to incorporate text from a specific source within a web page. In the most widespread situation, the text from one file is integrated in a different one, providing a website the sense that it's dynamic. As an example, if your website comprises of 10 web pages, five of them can have the content of any kind of file, for example horoscope.txt. As soon as you change this text file, the updated content will come up on all of the five web pages, which will enable you to revise your site much easier than if you had to update an element of all five web pages. Server Side Includes is in some cases utilized to contain the output of basic commands, scripts or functions as well - a hit counter that is shown on the site, the present date and time or the customer's IP address. Any webpage that utilizes SSI must have a particular extension - .shtml.