JVM Architecture

Virtual Machine

it is a software simulation of a machine which can perform operations like a physical machine. There are two type of virtual machines.

1. Hardware based or system based - It provides several logical systems on the same computer with strong isolation from each other. That is on one physical machine we are defining multiple logical machines. The main advantage of hardware based virtual machines is hardware resources sharing and improve utilization of hardware resources.
   Example - KVM(Kernal based virtual machine for linux systems), VMWARE, XEN, Cloud computing

2. Application based or process based - These virtual machines acts as runtime engines to run a particular programming language applications.
   Example -
   

   • JVM(Java virtual machine) acts as runtime engine to run java based applications.
     
   • PVM(Parallel virtual machine) acts as runtime engine to run perl based applications.
     
   • CLR(Common language runtime) acts as runtime engine to run .NET based applications.

Note - JVM is the part of JRE(part of JDK) and it is responsible to load and run java class files.