(z/VM or KVM on IBM Z). Microcode restricts IFLs from running "traditional" workloads, such as z/OS, but they are physically identical to other IBM Z processors
VM (often: VM/CMS) is a family of IBM virtual machine operating systems used on IBM mainframes System/370, System/390, zSeries, System z and compatible
z/OS, z/VSE, z/TPF, and z/VM are versions of MVS, VSE, Transaction Processing Facility (TPF), and VM that support z/Architecture. Older versions of z/OS