Native C code

Do you mean managed and native code?

Managed code execute under the control of the Common Language Run time(CLR). Example Managed C++, C#, VB .NET, etc

Unmanaged or native code execute outside CLR. Ex, Native C, C++, MFC, ATL, etc

The normal C\C++ code without .NET is called native programming. It may use Win32 API functions.

MSDN Overview http://msdn.microsoft.com/en-us/library/ms973872.aspx#manunman_rcw