PHP got traction because it was easier for hosting companies to set up shared PHP hosting and it was easier for non developers to add basic code to HTML pages.

PHP got traction because it was easier for hosting companies to set up shared PHP hosting and it was easier for non developers to add basic code to HTML pages. PHP was also at the right moment at the right time,just like MySQL and some people made it easy to install it on Windows, a platform too often ignored by language maintainers (try to write Ruby on windows, a (slow) pain in the ass).