Today nearly all programmers use the Advanced Programming Interface (API) to receive informations about given system values.

现在几乎所有的程序员都采用扩展程序接口（API）来获取操作系统信息。

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Method of Getting the system information is that calling the API functions to realize, through WMI programming, get the sys-tem information in VB.

获取系统信息的方法是调用API函数来实现，通过WMI编程，在VB环境中实现查看系统信息的功能。

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Jolicloud is a stripped down operating system that, instead of running software, connects to Web services using their application programming interface (API).

FORBES: The Disposable Operating System

Bug-for-bug compatibility is a problem, but breaking backward compatibility would be a much bigger problem, so even as the lowest layers of the operating system are revised and rewritten, the layers that applictions talk to (the application programming interface, or API) are carefully tested to ensure that no changes are visible to the application.

FORBES: What Is So Great About Microsoft?