Let Us Begin "storing"

Because this is the very first post of this new blog about things that I have known, I will stick to the topic that has been deeply rooted inside of me for so long now that I can't even remember how I ever got interested in it.

I'll stick to computers. And because I know a good amount about them, I'll further refine the search parameters to hard disk drives.

A fair bit of people will know that the first ever commercially available hard disk drive was made by IBM in 1956, and was called the IBM 350. this 60 inch long, 68 inch high and 29 inch deep monster had a capacity of about 4.4 megabytes. Compare that to a typical 3.5 inch format drive (4 in by 1 in by 5.75 in) of today that can store about 250000 times more data, and you will know how far we have come in the last 50 years or so.

For the personal computer, the first ever Hard Disk was made by Seagate, the company which is today the leading manufacturer and supplier of PC hard disk drives in the world. Introduced in 1980, it was called the ST-506, was 5 megabytes in storage size and fit into the 5.25 inch form factor popular at that time for floppy disks (We'll discuss floppy disks some other day, despite the fact that they have now entered oblivion with many other types of more flexible and reliable storage technologies emerging).

The HDD is a magnetic device, and despite the reduction in size and the huge increase in storage capacity, the underlying technology principle has remained same. It has however seen countless technical revolutions, and most these days quote the terms like magnetoresistance, Giant magnetoresistance (GMR), perpendicular recording and so on. We'll leave these for another day and for now concentrate on the basic technology.

Each HDD has a spinning spindle with a number of platters (disks made of non-magnetic material but coated with ferromagnetic substance - thus making the device primarily magnetic in operation), onto which directionally magnetized zones are created by the write heads, and the data thus stored in forms of binary bits, zeroes and ones depending on the direction of magnetization, is read by the "Read" heads by detecting the magnetization direction. The platters spin at very high speeds, usually higher than your car engine speed. And there are multiple platters, each with two usable surfaces and two sets of read-write heads to use 'em.

The growth in the storage capacities of disks hasn't been by adding more or larger platters as we can see by comparing the sizes given above. It has been made possible by shrinking each magnetized zone smaller and smaller into the electron microscope territory. Those big buzzwords you read about the technologies are all the ways to do precisely this and still get away with it.

And the spindle spinning speeds, they have gone from a respectable 1200 rpm on the original IBM 250, to 15000 rpm on the fastest available disks today. That's statistic alone is enough to get one's head spinning.

Approaching the end of today's lesson, it'd perhaps be best if I list the stats of the newest HDD that I have in my computer (a January 2007 piece), so that a few years hence I may laugh madly at it.

Hitachi Deskstar 7k320. 7200 RPM, 320 GB

We'll get back to HDD's some other day, when i'll perhaps touch upon somethings left aside today, and also post a glossary of related technical jargon.

PS. Next stop on this station - Cameras.