The site specializes in the Matroska (.mkv) format. Unlike MP4, MKV can bundle multiple audio tracks (e.g., dual audio), various subtitle files, and high-definition video all into a single file without massive file sizes.
Because sites like MKVMoviesHub rely on third-party ad networks, you need protection built into your portable environment. Install these add-ons inside the portable browser (they will save to the USB drive): mkvmovieshub com portable
Sites like MKVMoviesHub often operate by hosting links to pirated content. The "portable" aspect usually refers to: Introduction to MKVMoviesHub The MKV Container: The site