A structured breakdown of what Hyper-V is, how the hypervisor works, and how enabling it fundamentally transforms Windows into a root partition under a Type-1 virtualization framework.
Hyper-V is Microsoft’s built-in virtualization platform that allows the creation and management of virtual machines (VMs) in Windows environments. It is similar in concept to VMware or Oracle VirtualBox, but uniquely integrated into the Windows operating system itself.
Hyper-V is included in:
The Hyper-V technology is the hypervisor that powers the virtual infrastructure.
A hypervisor is a lightweight software layer that allows multiple operating systems to run simultaneously on the same physical hardware. This includes Windows, Linux, BSD, pfSense, and many more.
Hyper-V is always a Type 1 (bare-metal) hypervisor — even when installed on a laptop.
Whether installed on:
Hyper-V runs directly on the hardware layer, not inside the Windows operating system.
Once Hyper-V is enabled and the machine reboots, Windows is no longer the base operating system. It becomes the Root Partition (also called the Parent Partition).
The root partition:
Therefore, Windows serves as the management OS for the hypervisor, not the execution layer for the VMs.
Each VM runs inside a Child Partition — an isolated execution environment controlled by the hypervisor.
Child partitions:
Operating systems such as:
…all run inside child partitions.
Microsoft uses the term “partition” instead of “VM” because the architecture is container-based at the hypervisor level.
Before enabling Hyper-V, a Windows machine operates normally:
Hardware → Windows → Applications
When Hyper-V is enabled, the boot process changes dramatically:
Hardware → Hyper-V Hypervisor → Windows (Root Partition)
Hyper-V takes over the virtualization extensions of the CPU and becomes the true base layer of the machine.
Hyper-V “owns” the CPU virtualization extensions (Intel VT-x / AMD-V). Because it's a Type-1 hypervisor, it does not allow other hypervisors to run beneath it.
This is why VMware Workstation and VirtualBox often fail to start once Hyper-V is enabled.
In this lab, Hyper-V is enabled and configured on a Lenovo ThinkPad running Windows 11 Professional. Enabling the feature transforms Windows into a root partition operating under the Hyper-V hypervisor. All virtual machines used in this lab run as child partitions.