Final answer:
Virtualization software creates separate computing instances known as virtual machines, each with its own OS, sharing a single physical machine's resources.
Step-by-step explanation:
Virtualization software is used to create one or more separate independent computing instances, each with its own operating system, and we call each a virtual machine (VM). These virtual machines can run simultaneously on a single physical machine, sharing resources while operating as if they are distinct computers. This concept is a cornerstone of cloud computing and has revolutionized personal computing by allowing multiple operating environments on a single hardware platform, evolving from the era when a single desktop computer was shared by the whole family to now, when individuals can have multiple systems readily available.