The key to VM/ESA is the Control Program (CP)
The VM (Virtual Machine) operating system
More information on the CP component of VM
The Conversational Monitor System (CMS), although a component of the VM/ESA operating system, is itself an operating environment
More information about the CMS component of VM
What parts make up a VM or z/VM System?
What are the basic pieces of a VM and z/VM system, and how do they fit together? What services does VM provide?
What are issues related to supporting OS/390 or z/OS in a virtual machine?
An instance of Linux running under z/VM maintains its own security just as it would if it were running on a distributed system
Absolutely! Even though the mainframe itself typically lacks graphics display hardware, Linux can use the X11 network protocol to interact with a remote graphical display on another Linux or UNIX system, or on a dedicated X11 terminal