How the PHP programming language works underneath, and questions about the underlying C code.
PHP Internals
Tag purpose
The purpose of the php-internals tag is to indicate a question about the internals of PHP. Possible questions could be about how php references counting or copy on write. E.g. When you want to know what happens under the hood while doing things in PHP. It can also be applied to questions in the c tag that deal with extending PHP at the core. This tag should also be used for any questions about the Zend Engine powering PHP.
