vSphere is an enterprise level virtualization solution. It acts as the cloud computing OS managing a set of VMware ESXi-based hosts.

VMware's vSphere is a cloud computing virtualization platform built around the ESXi bare metal hypervisor. vSphere includes popular features such as HA (High Availability), DRS (Dynamic Resource Scheduling), vMotion (live migration of guests), and Storage vMotion (live migration of guests disks between datastores).

See the vSphere product page at vmware.com.