API (Application Programming Interface) is a set of rules, protocols, and tools for building software and applications. - It specifies how software components should interact, serving as an intermediary that allows two applications to communicate. - APIs are utilized in various contexts, from web-based services to operating systems and hardware interactions. - APIs facilitate development efficiency, integration, and innovation by abstracting complexity and exposing only necessary functionalities. Developers leverage APIs to access web services, manipulate data, and extend system capabilities without needing to understand or manage the underlying codebase, making them essential for creating interconnected, scalable, and flexible software ecosystems. **Declaration:** This content is [[human-made and ai-assisted]].