Remux 4k Today

If you have spent any time on torrent sites, Plex forums, or Reddit communities like r/hometheater, you have seen the term. But what exactly is a Remux 4K? Why are these files often 50GB to 90GB in size? And, most importantly, do you actually need one?

Source: A Remux file that has been re-encoded by a P2P group (like Tigole, QxR, or PSA). remux 4k