When a release is labeled it usually means:

Interstellar is Christopher Nolan’s 2014 sci‑fi epic. “Dual audio” indicates that the video file contains two separate audio tracks—typically the original English mix and a dubbed version (often Mandarin, Spanish, or another language). “4K” refers to Ultra‑HD video with a resolution of 3840 × 2160 pixels, offering four times the detail of standard 1080p HD.