Hi All (Experts)

   I m new to java and come from C ++ / perl background.
Can anyone tell me what exactly is JVM, JRE and when i run a class using java comand, what m i starting. When u say a VM instance, what does that mean ??
  I know it must be a very very basic question for u guys, but please help me or giude me to some resources on this.
thnaks
 -- shane

Hello shane,

JVM stands for, Java Virtual Machine, which is a java byte code interpreter.

JRE stands for, Java Runtime Environment, which includes the JVM and core Java Runtime Libraries.

When you execute 'java Your_Class' you are invoking the JVM - JRE, which loads / interpretes and runs your classes. Each time you invoke 'java' you are creating a new instance of the JVM to run your program. If you ran 5 programs, they all run in their own JVM.

TK.

Thanks TK.
It was great help. You really answered my question to the point.
One more small doubt - Is it right that when i start java.exe, i basically start JRE and JRE includes the intepreter JVM ?