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JVM & Byte Code

JVM is the main component of Java architecture and it is the part of the JRE (Java Runtime Enviroment) .It provides the cross platform functionality to java. This is a software process that converts the compiled Java byte code to machine code. Byte code is an intermediary language between Java source and the host system. Most programming language like C and Pascal converts the source code into machine code for one specific type of machine as the machine language vary from system to system . Mostly compiler produce code for a particular system but Java compiler produce code for a virtual machine . JVM provides security to java. 

The programs written in Java or the source code translated by Java compiler into byte code and after that the JVM converts the byte code into machine code for the computer one wants to run. JVM is a part of Java Run Time Environment that is required by every operating system requires a different JRE .
Ques 2:- JVM provides portability explain..? 
Implementations of java specification for a variety of CPUs and architectures provides the feature of portability. Foremost, without the availability of a JRE for a given environment, it is impossible to run Java software.JVM forms the part of large system i.e. the Java Runtime Environment (JRE). Each operating system and CPU architecture requires a JRE. JRE consists of a set of base classes i.e. an implementation of the base Java API as well as a JVM. The byte code format is same on all platforms as it runs in the same JVM and it is totally independent from the Operating System and the CPU architecture.
JVM is java interpreter as it converts the byte code into machine code for the computer one wants to run. 
JRE consists of a number of classes based on JavaAPI and JVM, and without JRE, it is impossible to run Java. So its portability really made it possible in developing write once and run anywhere software .

public class HelloWorld
{
public static void main(String arr[] )   {
System.out.println(" Hello World !");
}  }

  

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