The AudioContext is a key component of the Web Audio API, which allows developers to create and manipulate audio in web applications. It serves as the main interface for managing and controlling audio processing, enabling tasks like playing sounds, applying effects, and analyzing audio data. When an AudioContext is created, it initializes the audio system and provides a way to create various audio nodes, such as GainNode for volume control or OscillatorNode for generating sound waves. This structure allows for complex audio processing and real-time sound manipulation in web environments.