Microsoft Hyper-V, formerly known as Windows Server Virtualization, is a native hypervisor; it can create virtual machines on x86-64 systems running Windows.[2] Starting with Windows 8, Hyper-V superseded Windows Virtual PC as the hardware virtualization component of the client editions of Windows NT. A server computer running Hyper-V can be configured to expose individual virtual machines to one or more networks.
Hyper-V was first released alongside Windows Server 2008, and has been available without additional charge for all the Windows Server and Windows 8 and later. A standalone Windows Hyper-V Server is free, but with command line interface only
.

VMWare provides a powerful, flexible, and secure foundation for business agility that accelerates your digital transformation to hybrid cloud and success in the digital economy. With vSphere, you can support new workloads and use cases while keeping pace with the growing needs and complexity of your infrastructure. vSphere is the heart of a secure SDDC, securing applications, data, infrastructure, and access. Advanced security capabilities fully integrated into the hypervisor and powered by machine learning, provide better visibility, protection and faster response time for security incidences.
vSphere helps you run, manage, connect and secure your applications in a common operating environment across the hybrid cloud.

XenServer is an enterprise-class, cloud-proven virtualization platform that delivers all of the critical features needed for any server and datacenter virtualization implementation. A copy of the feature matrix that corresponds to the latest release can be found here. The following list summarizes some of the key capabilities of XenServer.
XenServer is based on the Xen Project™ hypervisor. The Xen Project hypervisor is a bare metal virtualization platform used by XenServer to deliver near native application performance for x86 workloads in an Intel and AMD environment.