Calling the Windows CE Operating System
The desktop version of the .NET Framework is very rich. It includes classes capable of performing advanced windowing, graphics manipulation, network connectivity, and much more. The .NET Framework is nearly a platform of its own, insulating developers from needing to interact with the operating system below. The price of this power and programming convenience is a footprint too large for most devices running Windows CE.
Users of the .NET Compact Framework can invoke the Windows CE operating system to perform actions that are out of reach by using the .NET Compact Framework alone. Situations where doing so would be useful include the following:
Performing cryptographic manipulations, such as encrypting data ...