oh yeah of course, it was a very theoretical "if i dig up this file in 30 years" - for the most part i access and update these files on the regular and have multiple backups. - but not much will beat stability of a format when things do go very wrong.

I can't find it now, but I remember reading about an organisation trying to archive work that had been on floppies and even when the data was read, the file formats were obsolete. so I wanted to draw the question on that kind of parallel.

as for the relationship format - definitely with visas/passports, a passport will have several visas on it, and will have taken journeys on it, etc. - again, i haven't done this _yet_ but it's been on my mind for a good year now and am just trying to take down my barriers to doing it.