Use this tag if a question is about VMware
VMware software virtualizes the hardware for a video adapter, a network adapter, and hard disk adapters. The host provides pass-through drivers for guest USB, serial, and parallel devices. In this way, VMware virtual machines become highly portable between computers, because every host looks nearly identical to the guest. In practice, a system administrator can pause operations on a virtual machine guest, move or copy that guest to another physical computer, and there resume execution exactly at the point of suspension.
From VMware Wikipedia Article:
VMware's desktop software runs on Microsoft Windows, Linux, and Mac OS X, while VMware's enterprise software hypervisors for servers, VMware ESX and VMware ESXi are bare-metal embedded Hypervisors that run directly on server hardware without requiring an additional underlying operating system.