[PHP] Re: include_once vs require_once

Basically, as I understand it, require() and require_once() are replaced during parsing—before code execution. And include() and include_once() are replaced during code execution. Thus, a required file is always imported into the file whereas an included file is only imported if the include() statement is executed.

Credit Note: http://ebullient.haaser.com/config/112/requireonce-vs-includeonce-in-php