This diagram summarizes the architecture of Windows. This architecture is the basis for the design of the Spotlight home page. Spotlight on Windows Home Page
The Process Manager keeps track of processes and their threads. It is responsible for passing the threads to run on the CPU, although this is done through the Kernel.
The Process Manager has access to the low level subsystems through the Kernel. It has no direct access to any hardware.
The Virtual Memory Manager is responsible for managing the physical memory. This is done through the Kernel.
The Virtual Memory Manager is also responsible for Application Virtual Memory Address space. Applications cannot talk directly to underlying systems such as Physical Memory or CPU. Applications use the Virtual Memory Manager to talk to underlying systems.
The Virtual Memory Manager maps part of its Virtual Address space addresses to space in a disk page file. The Virtual Memory Manager has no direct access to hardware however, and must therefore pass its request through the I/O Manager.
The I/O Manager is responsible for talking directly to hardware components such network and disk.
The Virtual Memory Manager is responsible for keeping track of the Virtual Address Space, and what addresses are allocated. The Virtual Memory Manager is also responsible for managing system virtual memory on disk. It does this by calling various I/O Manager functions.