JRuby is an implementation of the Ruby programming language atop the Java Virtual Machine, written largely in Java. It is free software released under a three-way EPL/GPL/LGPL license.
License: Open Source
jRuby is a Ruby interpreter that runs on the JVM and provides access to Java libraries, making it suitable for applications that need to integrate with Java. In contrast, Lua is a lightweight scripting language designed for embedded use and is particularly popular in game development for its simplicity and performance.