To answer this question, it might be better to say what the .NET Micro Framework is not: the .NET Micro Framework is not a traditional operating system with a managed code runtime (or virtual machine) layered on top. Instead, the SPOT team took the approach of coalescing the traditional functionality of an operating system—resource management, execution control, input/output (I/O)—with the traditional functionality of a runtime, which, not surprisingly, involves resource management, execution control, and I/O. What resulted was a bootable runtime. A basic architectural overview in Figure 1-2 shows the components that make up the runtime.
Figure 1-2. The basic architecture for .NET Micro Framework.