HTML: Server Side Includes (SSI) and .shtml Pages

Server Side Includes (SSI) are directives or commands placed in HTML pages, which are evaluated by the server while the pages are being served. They allow for content to be dynamically combined on an HTML page.

Apache must be configured to allow SSI. mod_include must be installed and enabled. If you have a site hosted by another company, their servers will typically be set up to allow SSI.

It is worth noting that for SSI to function, HTML pages with SSI commands must have the extension .shtml.

Here is example code you can use to include an HTML file within another. Very handy for including headers, footers, menus etc... that you re-use throughout your site.