JVM version refers to the installed JRE in your system and if you are in Windows, it should be loaded in System Environment (PATH), it will manage to execute the Java application in your system, especially it will install a plugin to your browsers (IE, Firefox, Chrome etc.). If JVM is not up-to-date, your machine can be hacked through browser such as via Java Applet as example. Make sure you have latest JVM - Test your browser via following link: http://www.java.com/en/download/installed.jsp
Diary of Java Programming language