Which layer of the OSI model does an Application Programming Interface (API) typically interact with?

An Application Programming Interface (API) typically interacts with the Application Layer of the OSI model. This layer is where end-user software and applications operate, allowing them to communicate with one another over a network. The Application Layer provides the necessary protocols and services for network applications, such as web browsers, email clients, and other software that requires network interaction.

APIs serve as intermediaries that enable different software applications to communicate and share data with each other. They define methods and data formats for requesting and exchanging information, facilitating interactions between different software applications that run at the Application Layer.

In contrast, the other layers—Physical, Data Link, and Network—handle lower-level functionalities like data transmission and routing, which are not directly involved in the API's operation. The focus of an API is on enabling application-level interactions, making the Application Layer the most relevant layer for its functionality.