Older PCs couldn't always boot from CD. In those cases, you needed a boot disk. It had just enough OS to get the cd drive working and allow for a full install. They also allowed for basic repair or maintenance tasks e.g. resizing the windows partition.

Veterans kept a couple about at home. Nothing like the catch 22. "I need a boot disk to fix my PC/I need my PC to make a boot disk."

When the OS is DOS you can easily fit the entire thing on a floppy.

Mac OS system 6 too, I think.

A lot of terraform and docker compose files could fit on a floppy still.

Actually, that might be a fun thing to play with. It might not have data. But you could back up a good amount of config and deployment information and have a system to restore data to.

Oh, there's a- Monkey in my pocket! And he's stealing all my change! His stare is blank and glassy I suspect he's deraaaaaanged!

You used to be able to get a whole-ass router that fit on 1.2MB in the late 90's.

Novell SPX routers also ran from a single floppy

Before bios supported bootable cd's you needed them to get the windows 95 install started.

That said, this was an obvious joke image :)