Unlike normal typewriters, the Selectric used a single use film ribbon. The letters typed were visible on the used ribbon. So each used ribbon essentially had a copy of every letter typed on it.
Because of this, at a defense contractor I was working for, the ribbons were required to be disposed of in a burn barrel. A burn barrel was a locked barrel where sensitive documents were disposed of so they could be securely destroyed.
At the time, working with folks on a presentation for a project on a Macintosh, the question came up on whether a LaserWriter cartridge should be similarly disposed of and destroyed. I think at the time it was decided “no”, though I don’t know today if a remnant image of the last few pages could be recovered from a modern cartridge or not.
I've had both Brother and Nakajima typewriters that do this, late models from the 90's.
(Which is funny, because one of the things I used my typewriter for was writing down the recovery keys for my password manager. In a darkened room with a white noise generator running, natch.)
In another lifetime the data center had two of these with the APL ball on them. I started a small business typing thesis papers into the computer then printing them off after swapping out the APL ball. It was a boon to candidates, they could get pages remade as they or their advisor made changes.
I was careful to work off hours and if a legit APL user wanted time, I quickly got off. I got caught when one night I left a carton of ribbons behind and the ops manager wondered where they came from.
They were brilliant for cutting reno/gestetner machine carbons. I think it is possible following users hated us for doing this but I may just be mis-remembering because the whole process was filthy. you never did agitprop without coming away covered in ink. (I was using this in my student days in the 1970s/1980s timeframe)
Unlike normal typewriters, the Selectric used a single use film ribbon. The letters typed were visible on the used ribbon. So each used ribbon essentially had a copy of every letter typed on it.
Because of this, at a defense contractor I was working for, the ribbons were required to be disposed of in a burn barrel. A burn barrel was a locked barrel where sensitive documents were disposed of so they could be securely destroyed.
At the time, working with folks on a presentation for a project on a Macintosh, the question came up on whether a LaserWriter cartridge should be similarly disposed of and destroyed. I think at the time it was decided “no”, though I don’t know today if a remnant image of the last few pages could be recovered from a modern cartridge or not.