Which virtualization type completely simulates a physical computer system?

Full virtualization is characterized by its ability to entirely simulate a physical computer system, allowing multiple operating systems to run concurrently on the same hardware as if they were running on separate physical machines. This is typically achieved through the use of a hypervisor, which creates a virtual environment that manages the hardware resources and presents a complete system to each virtual machine.

In full virtualization, guest operating systems are unaware that they are running in a virtualized environment, which means they function just as they would on dedicated hardware. This enables compatibility with a wide variety of operating systems and software applications, making it a versatile choice for environments where different OSes might be needed.

Other types of virtualization, like partial virtualization, paravirtualization, and OS-level virtualization, do not provide the same level of complete isolation and simulation. Partial virtualization may not fully virtualize all hardware resources, thus requiring some interaction or modification from the guest OS. Paravirtualization operates with a modified guest OS that collaborates with the hypervisor, which reduces overhead but limits compatibility. Lastly, OS-level virtualization runs multiple isolated user-space instances on a single operating system kernel, which is fundamentally different from simulating multiple independent physical systems.