I remember buying my first hard drive - 10MB (I thought I'd never fill a
30Mb one). 5¼" floppy disks soon got replaced by 3½"
ones (3" ones made a brief appearance). 3½" disks were used
to load programs onto the system, to transfer files and to create backups.
At their peak they cost just 5p each and could store 1.44Mb. They were still
prone to fingerprints, dust and magnetic fields though and those shutters
proved irresistible to being flicked until they sprung out and got stuck
in the disk drive or, if you were really unlucky, pulled out with a bit of
force along with the disk drive heads. As to reliability - well I lost
count of the number of times I've heard 'I can't get my file from this floppy
disk'. I've seen figures which indicate that there was a 20% failure rate for
I was once the proud owner of a laserdisc player which played 12" double sided disks. I had two of them, the BBC Domesday project which now can't be read since the disks got scratched and the computer used with the reader is long obselete. Sorry BBC - the 1086 version on paper far outlasted your laservision disks which took just 10 years to become useless! Today I know of just 1 working copy - in the national archives where one of the original 1086 versions is housed. (Now wouldn't you have thought that making a freely available version on Internet would be an excellent project for the EEC to fund? Update - it's now available on Internet here)
But then came CD-ROMs and CD-Rs and many floppies got replaced. My first CD-R drive was double speed and could store 650MB! According to the blurb fingerprints dust and scratches wouldn't stop them working. (I wish!) I now find that my early CD-R recordings can't be read. The problem seems to be that the reflective surface used in them is a very thin film of aluminium. Over time the slightly porus surface layer protecting it has allowed this to slowly oxidise to the point where it now contains tiny pinholes and dull spots, destroying the disk. A 'Gold CD-R' from that era where the reflective surface is gold rather than aluminium is just fine however.
Along came DVDs and DVD-Rs and now we could store up to 8GB at a speed that would have amazed us in 1995. In the meantime my hard drive in my laptop computer holds 500GB and a slightly bigger one can now hold terabytes of data. As for floppy disks drives- well I have a USB one somewhere. I don't use them since they seem to have gone up in price again, are painfully slow and have that 20% failure rate.
If I want to transfer files today I use a USB memory stick. Mine holds 32GB and has successfully survived being put through the washing machine. I also have micro SD cards which fit my phone and which can fit in an adaptor to use them in my computer. Standard size SD cards fit in my digital camera as well as the card reader slot in my laptop. SD cards are tiny! They are easy to lose and can become corrupted. My experience is that the less you pay for them the more unreliable they are as long term storage. Having said that I paid just £6 ($10) for a 4GB memory stick from a well known memory manufacturer and recently bought another for just £4.99 including delivery.
Today I no longer can read cassette tapes, 12" laserdiscs, 8½" or 5¼" floppies; my zip drive or tape streamer. I can still read a 3½" disc - if I can dind where I put that USB drive from wherever I put it.
But what of the future? How long will CDs and DVDs last? Not for long I think. Five years ago I predicted their demise. They are just too big and too easily damaged. Blue Ray, HD and Holographic DVDs will make a brief appearance but they won't last either. As a long term archive for precious data CDs and DVDs are a disaster unless they have that gold reflective layer. It's already obvious what the replacement will be. look for a credit card sized solid state storage device. Big enough to write the title of a movie on and with no moving parts. They'll get bigger and bigger capacities until hard drives are a thing of the past too. We already have 256Gb SSDs (Solid State Drives) which cost a lot less than my first 10 Mb hard drive!
Not convinced? Well here's a start!
* As a genealogist I've watched the demise of storage systems since the 1960s. Paper rots and becomes brittle, parchment is more durable but costs the earth and has a problem with mould. Even gravestones crumble and become unreadable. Remember 8 track stereo and Betamax video tapes? VHS is now obselete. Computer storage is constantly changing and today's method won't be readable in 10 years. My hard drive uses a SATA connector; a few years ago they all used IDE or SCSI. The only long term method seems to be storage on Internet (might not survive a breakdown of society) or perhaps the method still readable since the destruction of Pompeii - graffiti on a wall.