Seagate is now shipping 44TB hard drives, using lasers to increase stored data density. They expect to reach 100TB in the not distant future, all in the same form factor that has been standard for decades. My first personally owned hard drive was 10MB, an 8-inch "Winchester" in a case twice the size as the disk to include the power supply and other electronics. It died after a few weeks. I won't even detail the disks I dealt with for PDP-11s -- massive multidisk platters that we'd take in and out of drives the size of washing machines. A bit less than 100MB formatted for the RP04.
@lauren My first x86 machine was pieced together from other people's leftovers, and the pages of Computer Shopper. I got a 5MB Rodime drive, but had to get the interface card from a used parts ad. It required a _full_length_ RLL controller card. Old timers will recall the 5150 cases had those slots at the _front_ of the case to hold the front edge of these long cards.