Since Java contains its own operating environment, it is known as a "platform" in contrast to programming languages such as C and C++ that, once compiled, run natively and communicate with the ...

Wikipedia: A Java virtual machine is a program which executes certain other programs, namely those containing Java bytecode instructions….. JVM's are most often implemented to run on an existing ...

These languages provide various features that overcome some limitations of Java. For example, Groovy provides strong scripting features and the scripts can run on any platform that supports JVMs.

Frijters said IKVM is the Java VM on top of .NET and the open-source Mono project to create .NET-compatible tools and to run .NET apps cross-platform.