You're one of today's lucky 10,000.

Like another poster said, laser printers "back in the day" were freestanding computers with various communications interfaces that happened to have fancy paper handling and printing peripherals attached. In the case of the Apple LaserWriter, for example, it was arguably a more powerful computer[0] than the Mac machines of the day that were sending print jobs to it.

There were different ROM "personalities" available for laser printers, some of which came on pluggable cartridges.

Check these links out:

- https://www.pagetable.com/?p=1673

- https://www.pagetable.com/?p=1721

- https://www.pagetable.com/?p=1850

Michael Steil, the blogger responsible for those links, has done work extracting code and PostScript data out of some of those old cartridges. It's a really cool aspect of retrocomputing many people aren't even aware of.

[0] https://web.archive.org/web/20240404213221/https://lowendmac...

Up until like 15 years ago, lots of laser printers even had RAM slots as well. Populating them with extra RAM made them behave better when printing big PDFs and stuff.

In the dark ages, when printers were PostScript and more powerful (and expensive) than the computers which printed on them, you added fonts by installing additional hardware modules, similar to a game console cartridge.

They were ROM cards that stored extra typefaces or other PostScript functions.