In the case of electronic documents, the carrier’s stability is of lesser importance. Rapid developments in technology have resulted in the shortened commercial life cycles of digital audiovisual and other electronic data formats, putting the legibility of such documents at risk. Even in the case of stable carriers the lack of availability of dedicated hard- and software is the reason for the loss of data. Important data concerning space research, censuses, trade and health statistics are no longer legible and so become lost for ever. >> More