This refers to the resolution (Standard Definition). It means the video has 480 horizontal lines of vertical resolution. While the source was a high-quality Blu-ray, this specific file has been compressed/downscaled to a much lower quality, often to save storage space or for viewing on older devices.

As Earth faces an impending environmental disaster, a team of astronauts, led by Cooper (McConaughey), a former NASA pilot, embarks on a perilous journey through a newly discovered wormhole in search of a new home for humanity. Their mission takes them to the far reaches of the galaxy, where they encounter strange and wondrous phenomena, including a massive black hole and a mysterious force that defies explanation.