generate data for the web page whenever it is requested.
Server Side Includes applied to an HTML document provide interactive real-time features
such as echoing current time, conditional execution based on logical comparisons,
querying or updating a database, sending an e-mail, etc., with no programming or CGI
scripts.
An SSI consists of a special sequence of characters (tokens) on an HTML page. As the
page is sent from the HTTP server to the requesting client, the page is scanned by the
server for these special tokens. When a token is found, the server interprets the data in
the token and performs an action based on the token data.
