Server Unit
A server unit is a server-side script written in PHP code. You can create a new one from Home > New > HTML5 Builder Projects > Files > Server Unit.
Usage
To include the code of a server unit into another unit or a server page, use require_once:
require_once("unitfilename.php");
You can actually use 4 different functions to include a unit into another PHP script: require, require_once, include, include_once.