Mux is an API-first video platform that handles hosting, encoding, and delivery of videos to ensure the best streaming experience for viewers. It uses HTTP Live Streaming (HLS) to deliver adaptive streaming, which adjusts the resolution based on device and connection speed. This approach ensures high-quality delivery regardless of device or connection, making it ideal for various devices and networks. Mux processes video files into multiple renditions with different quality levels, creating a seamless experience for viewers. The platform supports HLS playback on web browsers, iOS, Android, and other devices, allowing developers to easily integrate adaptive streaming into their applications.