stands for virtual machine, the name and concept behind one of IBM’s two principal mainframe operating systems. In the VM environment, hundreds of individual users can make use of a large mainframe computer, and the operating system will maintain the illusion that all the computer’s resources are available for each individual user alone. Thus, the user can customize the user’s own virtual machine (or account) to access particular resources without having to worry about all the other demands being placed on the computer.
