Windows API or Windows SDK is a set of APIs, (application programming interfaces) available in the Microsoft Windows series.
Win16 was the first, 16-bit version of these APIs.
Win32 is the 32-bit API for modern versions of Microsoft Windows. The API consists of C functions implemented in dynamically linked libraries (DLLs), mainly in core DLLs: kernel.dll[?], user.dll[?] and gui.dll[?]. Although Microsoft's implementation of the Windows API is copyright, it is generally accepted that other vendors can emulate Windows by providing an identical API, without breaching copyright.
The Windows API was originally designed in the concept of object oriented. But computer powers at the time were largely limited and new APIs and enhancements have been a lot, it has lost some object-oriented aspects. Besides, it was somehow low-level[?], so many programmers prefer to use the MFC (Microsoft Foundation Classes[?]) other class libraries such as OWL (Object Windows Library[?]) of Borland for a more high-level approach.
Among other things, the Windows API contains the graphical widget toolkit used in different Windows versions.
The WINE project is an attempt to provide this API set for UNIX-like platforms.
Among common API functions are:
See also: DirectX, component object model, .NET
