Cost – every software is good in their places. But PHP as a backend language still uses now due to it’s low price. If you working for start-ups or small clients then PHP + MySQL provides all over good experience. You can even blogging website using word-press which owns near 78% market share globally when it comes to blogging platform, which again based on PHP. Along with compared to Java, Python developers cost always be high. But for the same project PHP takes low cost at least.
Old documentations – when you doing any project, it’s helps a lot.When you getting any problem in your current working project then old documentations will helps you a lot. You understand what actually you should do.
Easy – when it comes to easiness then PHP is much easier than others to learn and manage. Anyone can learn PHP within some weeks and make projects one by one and upload them into GitHub and boost their linkedin profile. Alomg with remembering syntax and coding process of PHP is much better than other languages.
Frameworks – due to old usage of PHP it has so many frameworks for making web application provcess much better for developers. Some popular frameworks are cakePHP, codigniter, laravel etc.
Nowadays laravel is most popular frameworks among others. It’s offers great security features then others. Making complex applications in PHP is good through laravel.
Great developer support – due to old language it’s has a strong community base everywhere. You will get any instant help from your colleagues or online community like from stack overflow, Quora or even facebook.
Cross platform & open-source : it’s true PHP is open-source language so generally for using PHP for commercial purpose you don’t need to pay any amount. Along with PHP application can run on any platform if it installed PHP running server into this. So if yo develop any PHP web-app in windows or Mac then it easily run on Linux server.