What Is an API?

API (Application Programming Interface, application program interface) are some predefined functions, or refer to the convention of connecting different components of a software system. ^{[1] The} purpose is to provide applications and developers with the ability to access a set of routines based on certain software or hardware without having to access the source code or understand the details of the internal working mechanism.

Internet-based applications are becoming more and more popular. In the process, more sites open their resources to developers to call. Externally provided API calls make the content more relevant between sites, and these open platforms also bring greater value to users, developers, and small and medium-sized websites.

Opening up is a development trend, and more and more products are opening up. Websites cannot keep users by restricting them from leaving, open

As stated in "What is an API", API functions are contained in the system directory

Suppose you want to

Remote procedure call (

The API interface belongs to an operating system or program interface, and the GUI interface belongs to a graphical operating system. Both are direct user interfaces. Sometimes companies use APIs as their public open systems. In other words, the company formulates its own system interface standard. When it is necessary to perform system integration, customization, and program application, all members of the company can call the source code through this interface standard. This interface standard is called an open API. .