Windows API The Windows application programming interface (API) enables you to develop C/C++ applications that take advantage of the power of Windows. Using this API, your applications can run successfully on all versions of Windows while taking advantage of features and capabilities offered by each version. The Windows API includes the following functional categories: Administration and Management Install, configure, and service applications or systems. Diagnostics Troubleshoot application or system problems and monitor performance. Graphics and Multimedia Incorporate formatted text, graphics, audio, and video. Networking Communicate between computers on a network and manage access to shared resources. Security Enable authentication, protection of sharable objects, access control, rights management, and security auditing. System Services Access resources and operating system features such as memory, file systems, devices, processes, and threads. Windows User Interface Create and manage windows that carry out tasks necessary to support interactions with the user. For information about the .NET Framework API, see the Quick Technology Finder for .NET Framework 4 and the .NET Framework Class Library.