Blu-ray disc

A single-layer Blu-ray disc can fit up to 27GB; this is enough for about four hours of high definition video with audio. A dual-layer Blu-ray disc can fit up to 54GB, enough for eight hours of HD quality video. Recently, TDK unveiled a prototype four-layered, 100GB Blu-ray disc. Theoretically, a Blu-ray disc can go up to capacities of 200GB when it achieves eight-layers.