Troy on Nostr: These are 5.25" floppy disks. Before that were 7", and I think there were larger ones ...

These are 5.25" floppy disks. Before that were 7", and I think there were larger ones before that. Single-sided disks were cheaper than double-sided. You could tell them apart by a notch in the side, where the drive would lock it into place. Double sided disks had a notch on the left and right, so it could be flipped over and inserted properly. Single-sided disks just had a notch on one side.

The funny thing is, if you cut a second notch into a single-sided disk, it magically bacame a double-sided disk! 😀