system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When the twin towers fell, what types of paper records were lost?

They called it the 'World Trade Center'. 
Surely back in 2001 not much, if any, was backed up on computers (outside of the building).
Both buildings must have had hundreds of miles of paperwork that was lost and unrecoverable. 
Did many businesses lose records? Did anyone's credit card debt disappear? Did the US government leave their bills to China in there?

I'm very curious as it seems to be a topic that is never covered.

Edit: Perhaps I phrased it badly, is it bad etiquette to change the title? 
I was also thinking about whether there were offsite backups for the computer records.
gpt
You are mistaken about how computerized things were in 2001. All major businesses were deeply computerized by that time. In fact, you may recall there was something called the y2k crisis, in which businesses were terribly afraid their computers would go down when the year switched from 1999 to 2000.