What is the API of the computer? Is it the port?

API is the abbreviation of application programming interface, which refers to the application programming interface. The API contains a series of defined functions. Using encapsulated API functions can easily access hardware, obtain a mature program architecture, use complex mathematical functions and so on. It can improve the portability of the program, reduce the complexity of development and improve the stability of the program. Almost all programs need to use API, including API libraries written by other individuals or organizations, or APIs packaged inside the project.

The following figure is the API description (partial functions) of the core system functions provided by Microsoft. Through this document, you can know which interfaces can be used, what they are used for and how to use them.