It sounds like you’re looking for an —what they are, how they differ from other video formats, and why they’re popular in torrenting communities.

Here’s a concise breakdown: A remux (re-multiplex) is a video file created by taking the audio, video, and subtitle streams directly from a Blu-ray, UHD Blu-ray, or remastered source and repackaging them into a container (usually MKV) without any re-encoding.