Amazing when you think that when I first started with computers - I built my first one, a Sinclair ZX-81, in 1982 - I was using cassette tapes for data and program storage. Not fast, and when you wanted to access something, the further from the beginning of the tape it was, the longer you had to wait ... and not the nanoseconds we think about with today's hard drives.
My first "PC Compatible" computer used a 5.25" floppy drive for storage. Better, but still only stored about 100 Kb. (I did have an 8 inch floppy drive for my ZX-81 at one point. It loaded CP/M - a predecessor of DOS - and I was able to run Wordstar on my Sinclair, but that was more something that I reviewed in Computer Shopper than used on a daily basis.)
I wanted something bigger, so I bought a 10 Mb hard drive on a card and installed it in the computer. Wow! A whole 10 Mb! I couldn't even imagine under what circumstances I could ever want more than that. Until that drive got filled up. Oh, I kept it clean, removed junk files, defragged the drive, but the day came that I had no more room on the drive. You see, I had started working with graphics since I had started a desktop publishing business of my own. By the time I was working full time as a graphic artist and electronic layout specialist in the publishing industry, I was creating files that themselves were many times larger than that 10 Mb hard drive.
Today, I installed a new 2 Tb drive on my Mac, just to act as a backup drive for all the other drives on my network. Yes, I said network ... at home. In our house we have an iMac, a PC laptop and a PC netbook, all of which not only have their internal hard drives, but store data on drives that are available to all of our computers via our home wifi setup. Today, we can access our music, documents, photos, graphics or movies from any of our computers. Many of these files are quite big. At the moment, I have a total of 3.5 Tb of storage on the network, having added a 2 Tb drive last week. Yesterday, I added another 2 Tb drive to my iMac to act as a back-up drive, bringing the total to 5.5 Tb. Oh, and I have a 320 Gb drive which I use with my laptop when I travel. I can, however, access my home network drives via the internet when I am not home, but that is usually overkill.
Yet, I have no illusions that at some point, that will seem as inadequate as the 10 Mb drive on a card ... or the cassette storage I used before that. <sigh>
How much/what type of storage/backup do you use?