This is the most critical part of the equation. x264 is a software library for encoding video streams into the H.264/MPEG-4 AVC format. In the late 2000s, x264 revolutionized file sharing. It allowed encoders to compress video files to a fraction of their original size while maintaining visual fidelity that was imperceptible to the average viewer on a standard monitor.
The YIFY release of Back to the Future is legendary because it handles the film’s specific challenges perfectly: