Paper survives ; digital files do not.
A in a dry room is readable after four centuries with no intervention.
A file from twenty years ago may be unreadable because the format is .
Preservation in digital form is therefore an activity rather than a condition.
It requires to new formats, checks against and copies in separate places.
Each of those steps needs a budget line that must be renewed by somebody who was not there at the start.
Institutional memory, not technology, is the binding constraint.
The most fragile material is not the oldest but the most recent.
Government decisions now sit in messaging applications that keep nothing by design.
Historians of this decade will have fewer sources than historians of the nineteenth century.
rules were written for publications and adapt badly to a feed.
Web archives capture a fraction, and the fraction is biased towards what is public and .
Private groups, which is where much of public life now happens, are absent.
There is no technical solution to this, only a records policy that somebody enforces.
The paradox is that the era producing the most data may leave the thinnest record.