A Sound API (Application Programming Interface) is a set of tools and protocols that allows developers to create, manipulate, and manage audio in software applications. It provides functions for playing sounds, recording audio, and processing sound effects, making it easier to integrate audio features into games, music apps, and other multimedia software. By using a Sound API, developers can access various audio formats and control playback settings, such as volume and pitch. Popular examples of Sound APIs include Web Audio API for web applications and OpenAL for game development, enabling rich audio experiences across different platforms.