An AV Switcher is a device used to manage multiple audio and video sources, allowing users to select which source to display or output. It is commonly used in settings like live events, presentations, and broadcasting, where seamless switching between different media sources is essential. These switchers can handle various inputs, such as cameras, computers, and microphones, and route them to a single output, like a projector or television. This functionality helps streamline the production process and enhances the overall viewing experience by providing smooth transitions between different content sources.