A Logical Machine (LM) is a simulated machine running on a real machine. Logical machines run their own Logical Machine Operating System (LMOS), which in turn manages the logical machine and the user processes. Each logical machine has its own, independent LMOS.
The connection between a logical machine and the real machine is managed by the Logical Machine Monitor (LMM) which provides services in terms of hardware access to all logical machines running on a real machine. To perform certain hardware-dependent operations, a LMOS would call the LMM in the way user programs issue system calls. Figure 1 shows a diagram of logical machines running on a real machine.
Figure: A logical machine in its environment