virtual machine LastModified: Wednesday, April 25, 2007
A self-contained operating environment that behaves as if it is a separate computer. For example, Java applets run in a Java virtual machine (VM) that has no access to the host operating system. This design has two advantages: System Independence: A Java application will run the same in any Java VM, regardless of the hardware and software underlying the system. Security: Because the VM has no contact with the operating system, there is little possibility of a Java program damaging other files or applications. The second advantage, however, has a downside. Because programs running in a VM are separate from the operating system, they cannot take advantage of special operating system features.
The Java Virtual Machine Specification Description of and link to the online version of the book entitled "The Java Virtual Machine Specification" by Sun's own designers of the Java VM, Tim Lindholm and Frank Yellin. Yahoo!'s parallel virtual machines page Yahoo!'s directory of parallel virtual machines. Understanding Hardware-Assisted Virtualization Hardware-assisted virtualization changes the access to the operating system itself. x86 operating systems are designed to have direct access to system resources to run. With software virtualization the VMM emulates the required hardware to the operating system. Webopedia's Quick Reference: Virtualization: All About Hypervisors As virtualization — or at least talk of it — spreads through the enterprise, the word hypervisor is popping up everywhere. To understand what a hypervisor is, you first have to have a basic understanding of system virtualization.	related categories: Operating Systems Programming Virtualization related terms: J2EE Java Jini JIT JNI JVM operating environment virtual virtual machine monitor virtual machine server virtual network computing virtualization