PHP is a widely-used, open-source scripting language used for developing web applications and dynamic websites. It is a server-side scripting language that can be used to create dynamic web pages, applications, and content management systems. PHP code is embedded into the HTML of a web page and is executed on the server. PHP can be used to access databases, create user authentication systems, generate dynamic page content, and create cookies. It is a popular choice among web developers because it is relatively easy to learn and use, and it is well-supported by a large community of developers.
Can do everything PHP does. Usable for all types of software, not just web. Super slim, the opposite of bloatware. Summary: maximum benefit, minimum overhead.
Discontinued It seems that the project is no longer being developed and the wiki has not been updated since February 2015. The latest version, 0.9.6, released in December 2013, can still be downloaded from the official website.
Javascript is for front-end code