Jack Skinner has posted his latest "roundup" results of the most popularly installed versions of PHP across the web. In the post he looks through the percentage of installations for each version and how many are "secure" (currently supported and in a popular/stable linux distribution).

Last year, Anthony Ferrara posted an excellent round up of PHP versions in the wild, specifically focusing on the volume of un-patched versions running production websites. Even as an estimate it was an eyeopening moment for many people.

Using data from w3techs and, while the raw data isn't posted, what's there is good enough for an estimation. He talks some about the definition of "secure" in the context of the results and lists the current versions of several popular linux distributions and the versions they support. His results are then grouped by minor release and created some graphs for the results to help with visualization. The remainder of the post shares these results for PHP versions 5.6, 5.5, 5.4, 5.3 and yes even 5.2/5.1. The results end with overall numbers/graphs of the most widely installed versions and what percentage of those are considered "secure". With PHP 7 just released the results are a little discouraging but it is good to see things trending the right way since last year's results.

Adam Culp has posted his own look at some of the PHP usage statistics that are out there and how they can be interpreted.

Every once in awhile I stumble across someone who is trying to find their way and decide what they will do in their career. As the organizer of a PHP user group I see many new developers passing through. Of course I always speak of how strong PHP is in the web markets, and encourage new web developers to pursue PHP as a tool in their box of goodies. Because as a web developer it would be a career limiting move to not have any knowledge of PHP. Here is why...

He shares a few different sources including w3tech's overall and PHP-specific information (PHP5 specific here) and the current results of the TIOBE index showing language popularity. For each he talks some about what the results mean (and don't mean) and how, if you're a "professional developer" you should, at the least, know PHP - the most dominant language in the web space.