One doesn’t have a hard drive. Just two 5 1/4 drives so you can boot up and run programs off of. Also a compaq sewing machine case computer. Sewing machine case refers to the shape of the portable computer.

Portable with 2 5.25 one sided discs. You booted up individual programs on one disc and kept your data on another. She had it hooked to an AB switch for printing. Draft stuff to a dot matrix and daisy wheel for letters and stuff.

I used DataBase4 at work in the early 90s. I copied the executable program onto a 3.5 floppy and had room for files left over. Programs were a lot tighter written.

then i got a 10 meg open frame segate that was problematic when the weather shifted or i installed an or remved an app.

I've only got one eight inch floppy drive but haven't had any occasion to use it for many years. I'm a little reluctant to turn it on now. If it didn't work I might find myself going down an Alice in Wonderland rabbit hole of troubleshooting and repairs.

Here's a guy who works on computers older than those I've got:

https://www.youtube.com/@UsagiElectric

Some of his computers use the large hard disk packs you describe.

Most of my Atari 8 bit hardware still works but I'll confess I hardly ever power it up any more. It's a lot easier to emulate it on my Linux desktop.

I was always fond of 3.5" drives. They were very Star Trek to me. That's probably why I like flip phones too.

We had a CPM based computer at work that had drives for both 8" & 5¼" discs.
I wrote a couple programs to estimate heat transfer constants based upon molecular structure and had them saved to disc.
When the little hard shell type came out, they were for the first 2 Macs the company had.
For several years, I used a sampler in my keyboard rig that stored the sounds on floppy discs. I still have that rackmounted sampler, though I upgraded to a hard drive based (with better audio quality) a long time before I quit performing.

First ones were the soft 5 1/4 or so floppy, used with NorthStar controller (my memory may be vague on all these things) then 8 inch floppies in Shugart drives with Tarbell controller (still have the cards but no more of those drives)

Big coup at work was when there was some horrendous way to get digitized interferometer data into the IBM mainframe.

I set up an Altos CP/M machine with a program that wrote to the 8 inch floppies in IBM 3740 format. The folks using it didn’t mind the steps that it took, because it saved them many more steps than the orevious way. Write it out, and the IBM sysops read it in. Bingo.

I can still read and write the 3 1/2 inch floppies with a USB drive. Another for iomega disks, but all the other formats (like Syquest) are gone.

As I moved on to newer stuff, I gleaned all the data off old disks, which mostly became obsolete, at least as far as my collection goes.

The iomega (zip) were said to be able to survive a trip in the washing machine, but I never tested that proposition.

Everything above subject to memory correction.

You can run CP/M in emulation nowadays. Same for MacOS 9 and HyperCard.

computers at the library.

...but are you referring to these big removable disk packs? You loaded them into a big washing machine sized thing and twisted to remove the dust cover? We had a room full of these by the... mid 80s. I don't think I'd be able to lift one of these things nowadays. I remember thinking these were the epitome of high tech.

This was basically Paul Allen's personal collection of computers...and that guy had some serious iron in his collection.

Anyway, I'm in the mainframe room they had there looking at the IBM version of the CDC pack drive that holds the disc pack in your photo just searching all over the damned thing and the docent came up...

"Do you have any questions?"
"Yeah. Where's the head switch on this unit?"
"Why would there be a head switch?"
"Because if you can't turn the head motor off you can't purge the disc before you start using it, and that's pretty important."
"How in the hell did you know that? When did you become a mainframe sysop?"
"1989, in the Army."

So we spent a very pleasant hour talking about real computers. He'd spent his career working with IBM 360s and 370s; I was mostly a Unisys guy but we had pretty much everything - when the government had a mainframe they didn't know what to do with they'd dump it on a field station so we had all this weird crap that was old enough to vote...and we were using it in production.