A new way to stop digital decay

摘要

When future historians turn their at-tention to the early 21st century, electronic documents will be vital to their understanding of our times. Old web pages may not turn yellow and brittle like paper, but the digital documents of today's culture face a more serious threat the disappearance of computers able to read them. Even a relatively simple electronic item, such as a picture, requires software to present it as a visible image, but 100 years from now, today's computers will have long since become obsolete. More complex items, like CD-ROMS or videos, will be unreadable even sooner. In 1986, for example, 900 years after the Domesday book, the BBC launched a project to compile data about Britain, including maps, video and text. The results were recorded on laserdiscs that could only be read by a special system based around a BBC Micro home computer. But since the disks were unreadable on any other system, this pioneering example of multimedia was nearly lost for ever. It took two and a half years of patient work with one of the few surviving machines to move the data on to a modem PC (it can be seen online at www.domesday1986.com).