> I never read how the zip drive can achieve 100x or more capacity than the floppy. What is the engineering feat that allowed this?
Improvement in production processes and materials (e.g. magnetic coatings) allowing smaller tracks and smaller more precisely positioned heads. The 3 1/2 floppy dates back to 1983, the high-density 1.44MB to 1986, the Zip drive was released in 1994.
A “super high density” 20 MB floppy had already been attempted in 1990, and the LS-120, which had the exact same dimensions as a 3.5” floppy (and could read those), launched in 1996, so it was not really exceptional at 6 doubling in 8 years from the 1.44MB floppy.
Also it was expensive, part of that was the lower scale and lack of competition but the increased production requirements were also a factor, Zip drives and media had tighter tolerances.
The click of death was because when the head got misaligned the drive would return it to the home position, if part of the drive had failed the head would never realign so the drive would keep trying, producing a characteristic clicking sound. HDDs can develop the same, but it’s less common than it was on Zip drives. The tighter tolerance were most likely a factor, it was more likely for a zip to age out of tolerance and develop terminal misalignment.