DIGITAL technology could turn the 21st century into a new dark age lost to history, a leading internet pioneer has warned.

As operating systems and software get upgraded, documents and images stored using older technology are becoming increasingly inaccessible, said Dr Vinton “Vint” Cerf, vice-president of Google. In centuries to come, historians looking back on the present era could be confronted by a digital desert comparable with the dark ages — the post-Roman period in Western Europe about which relatively little is known because of the scarcity of written records.

Dr Cerf, who also has the title of chief internet evangelist at Google, said: “If we’re thinking 1000 years, 3000 years ahead in the future, we have to ask ourselves, how do we preserve all the bits that we need in order to correctly interpret the digital objects we create?

“We are nonchalantly throwing all of our data into what could become an information black hole without realising it.

“The 22nd century and future centuries after that will wonder about us but they’ll have great difficulty knowing much because so much of what we’ve left behind may be bits that are uninterpretable.” He urged people to think about printing out their treasured photos and not rely on storing them as memory files.

“In our zeal to get excited about digitising, we digitise photographs thinking it’s going to make them last longer, and we might turn out to be wrong,” he said.

“I would say if there are photos you are really concerned about create a physical instance of them. Print them out.” Dr Cerf was speaking at the annual meeting of the American Association for the Advancement of Science in the Silicon Valley capital, San Jose, California.

To illustrate his point, he referred to an “amazing book” by American Pulitzer Prize-winning historian Doris Kearns Goodwin, Team Of Rivals: The Political Genius Of Abraham Lincoln.

Her material was obtained by scouring libraries for copies of written correspondence between Lincoln and the people around him. Dr Cerf said: “Let us imagine that there’s a 22nd-century Doris Kearns Goodwin and she decides to write about the beginning of the 21st century and seeks to reproduce the conversations of the time.

“She discovers that there’s an awful lot of digital content that either has evaporated because nobody saved it, or it’s around but it’s not interpretable because it was created by software that’s 100 years old.”

The problem also had serious implications for the storage of legal documents needed to be kept for long periods, he said. One possible solution was what he called “digital vellum”, a concept now being explored by computer scientists at Carnegie Mellon University in Pittsburgh.

This involved taking a digital “snapshot” at the time an item is stored of all the processes needed to reproduce it at a later date, including the software and operating system.

The snapshot could then be used to reproduce the game, picture file or spread sheet, on a “modern” computer, perhaps centuries from now.