Unlike the regular M-DISC, which has a standard capacity of 4.7GBs, the Blu-ray M-DISC features 25GB of storage space, and obviously requires a Blu-ray disc drive to work. It still offers the other features of the DVD M-DISC, and is aimed specifically at individuals who require both high-capacity and a long lifespan for long-term data archival.
Millenniata says using an M-DISC is equivalent to engraving data in a stone, both because the disc lasts 1000 years and because it is virtually impervious to certain conditions that render a regular DVD or Blu-ray corrupted. The M-DISC is capable of handing exposure to heat, light, and humidity without degrading. The lifespan was determined via testing under the ISO/IEC 10995 Standard.
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