My observations for the popularity of PHP are this:
1) It's old. You're alternatives to PHP 12 years ago are all bad. The most popular alternative was perl CGI scripts.
2) Since it's templated, it feels more like markup . Someone with absolutely no programming background can go: HTML -> HTML with a javascript "onclick" handler pasted from the web -> HTML with a bit of PHP pasted from the web -> writing my first original PHP code
1) It's old. You're alternatives to PHP 12 years ago are all bad. The most popular alternative was perl CGI scripts.
2) Since it's templated, it feels more like markup . Someone with absolutely no programming background can go: HTML -> HTML with a javascript "onclick" handler pasted from the web -> HTML with a bit of PHP pasted from the web -> writing my first original PHP code