A JVM is able to execute the .class file which may be generated in any platform (like Windows, Linux).So JVM makes java platform independent.
A java virtual machine is a virtual machine that enables a computer to run a JAVA program as well as program written in other languages.
A Java Virtual Machine is a program whose purpose to execute other programs.
A Java virtual machine (JVM), an implementation of the Java Virtual Machine Specification, interprets compiled Java binary code (called byte code) for a computer’s processor (or “hardware platform”) so that it can perform a Java program’s instructions.
The Java Virtual Machine Specification defines an abstract rather than a real machine or processor.
When you run a Java program, it runs as a thread within the JVM process. It is the JVM’s responsibility to load your class files, verify code, interpret them and execute them.