Virtual Machine

A virtual machine is a software-based emulation of a physical computer that runs its own operating system and applications as if it were a separate machine, while actually sharing the underlying hardware of a single physical host with other virtual machines. IBM's Cambridge Scientific Center developed the technique in the late 1960s with the experimental CP-40 system and its successor CP-67, which let a single mainframe present multiple users with what each believed was their own dedicated computer, a capability IBM commercialized in its VM family of operating systems through the 1970s. The idea moved from mainframes to ordinary desktop and server hardware decades later when the company VMware, founded in 1998, released VMware Workstation in 1999, and virtual machines are now a foundational technology behind modern data centers and cloud computing, letting one physical server run many isolated operating system instances at once.