Storage media such as DVDs, CDs and hard drives have a lifespan of about ten years. How can we ensure that key moments of life captured on digital photos will still be preserved in 20 or 30 years’ time? Or that in 100 or 500 years, information on the storage locations of nuclear waste and the necessary safety precautions are still available? How can data be stored permanently? Each potential solution presents a new scientific and technological challenge. What will replace USB flash drives? DNA? Quartz? Or will we have to go back to the sheets of paper that proved their worth over the centuries?