What gives java it's "write once and run anywhere" nature (CoreJava)

Question :What gives java it's "write once and run anywhere" nature? (CoreJava)
Answer :Java is compiled to be a byte code which is the intermediate language
between source code and machine code. This byte code is not platorm
specific and hence can be fed to any platform. After being fed to the JVM,
which is specific to a particular operating system, the code platform
specific machine code is generated thus making java platform
independent.