Kindly ignoring the snide fact that, yes, git wasn't available in 1993, I'll point out that ASCII has been around since, what, the late 1960's? Of course, I will admit I was being a bit snarky too, but backups have been around forever, and text compresses really well. Of course, I can appreciate the permanence of ink, or even stone as a media (http://books.google.com/books?id=CgeHW-geducC&lpg=PA6...).
