A Virtual Machine is a software computer that runs an operating system or application environment, just as physical hardware would. The end user has the same experience on a VM as they would on dedicated hardware.
Essentially, a VM is a machine within a machine. By running VMs, a hardware computer can run multiple instances of the same operating system. Applications running on separate instances cannot interfere with each other, so if one app crashes, it will not affect apps on other VMs.
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