What version of PHP is learned in the course?

Hi there,

As for the topic subject, what version of PHP is used in the course here on Codecademy? I know that during the years several versions came out and some things changed, and sometimes course providers don’t have the chance to catch up with the changes, so I’ve been wondering what PHP is learned here on Codecademy?
And how does the version affects one learning the language? In terms of employment, most commonly used frameworks, etc.

I couldn’t find this info in the course description or on the forum.

Thanks to anyone that can help me with this.