Languages

The word Java, by itself, usually refers to the Java programming language which was designed for use with the Java Platform. Programming languages are typically outside of the scope of the phrase "platform", although the Java programming language is listed as a core part of the Java platform. The language and runtime are therefore commonly considered a single unit.
Nevertheless, third parties have produced a number of compilers or interpreters which target the JVM. Some of these are for existing languages, while others are for extensions to the Java language itself. These include:
Clojure
Groovy
JRuby, a Ruby interpreter
Jython, a Python interpreter that include jythonc, a Python-to-Java bytecode compiler
Rhino, a JavaScript interpreter
Scala