Virtualization has its roots in the mainframe era of the 1960s, and is particularly associated with IBM, whose CP-67/CMS was the first commercial mainframe operating system to support a virtual machine architecture in 1968. (CP stands for Control Program, while CMS stands for Console Monitor System; CP created the virtual machines, which ran the user-facing CMS.)
PC-era virtualization kicked off in 1987 with Insignia Solutions' SoftPC, which allowed DOS programs to run on Unix workstations. A Mac version that also supported Windows applications appeared in 1989, followed by SoftWindows bundles containing SoftPC and a copy of Windows. Another notable PC virtualisation pioneer was Connectix, whose Virtual PC and Virtual Server products were acquired by Microsoft in 2003 and re-released in 2006 and 2004 respectively. VMware, the current market leader in virtualization, released its first product, VMware Workstation, in 1999.
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