I'm drinking this in ... great stuff. I was at a zoo today and suddenly realized that the term "fledgling" has an orinthological origin -- it's not a metaphor to apply the term to birds. It's amazing that I've been using that word for decades and it never occurred to me. Thanks for similarly making me understand the term "hard drive crash".

A post on netwoman reads:

Dale Spender and Helen Fallon (1998) also assert that terminology such as 'abort', 'chaining', 'thrashing', 'execute', 'head crash', and 'kill' portray negative images of sex and violence to women, creating an uncomfortable and unfamiliar terrain. http://www.netwomen.ca/Blog/2003_09_01_archive.html#106427418616569858

I haven't read the specific article referenced, but I wonder if your description of the technology of computers as a physical environment (on the micro level) would place the percieved violence of computer terminology into another context.

I have lost so many files to my hard drive, and I know I've been lazy in backing up a hard drive at home that's dying, so I know I'll suffer more data loss. I imagine if I were to get cancer, I'd want to know all I could about the disease, just so I could know what it was doing to my body. I realize that "my hard drive crashed" is the modern equivalent of "my dog ate my homework," but non-geeks are generally mystified by what goes on in their computers.

"Incidentally, platters spin counter-clockwise; note that this means that head actually reads and writes right to left."

1) Possibly a missing word... should that be "this means that THE head"?

2) I remember once some old college friends of mine had a disagreement about when a shower curtain was "open" -- was the curtian "open" when it was crumpled up to permit access to the shower, or whas the curtain "open" when it was unfolded, permitting the curtain to dry?

Maybe I just can't visualize the "right to left" motion you describe. When I watch the second hand sweeping around the face of a clock, from my perspective the hand is moving left to right as frequently as it is moving from right to left. A clock has a conventional neutral position -- 12:00 -- that can be a reference point to describe the motion of the second hand as starting off moving from left to right (even though it makes as much sense to say the second hand starts off moving from up to down). But the stylus of a phonograph album is probably a better analogy for the read/write head in a hard drive, and that stylus is generally on the right side, not either on the top or bottom -- so the vinyl is moving vertically through the position occupied by the needle. I presume that placement of the stylus is because most people are right-handed.

Please don't interpret my questions as nitpicks -- and if the notes or other sections will handle any of my objections, I'm happy to wait for the book. But I am curious... is there a similar reference point in a hard drive that makes the "right to left" perspective obvious?

Thanks for this, Dennis--just the kind of feedback I was hoping for in terms of letting me know where the techical description breaks down. "Right to left" because the head will be motionless as the surface of the platter, spinning counter-clockwise, rotates past underneath; if you visualize that it necessitates a right to left read/write pattern.

Hmm... that works if you envision the r/w head like the hand of a clock pointing up to 12. But if you envision the r/w head as a hand pointing down to 6, then wouldn't it be equally possible to say that the surface is moving past the head left to right? I'm not saying that it makes more sense to envision the r/w head as a hand pointing down, but I don't know why it WOULD make more sense to envision a hand pointing up. Even saying something like "hard drives are conventionally mounted such that the head reads and writes from right to left" would satisfy my idle curiosity.

Oh, I see what you're asking . . . the head remains in a relatively fixed position at the end of the actuator arm. It seeks to find tracks, but waits passively for sectors to spin past--it doesn't circumnavigate the platter. So the head does in fact align at a roughly 12 o'clock position, and it's more or less fixed there except for some lateral movement.

Next time you a drive fails and you're done with it go ahead and break it open.

OK, that answers that question... thanks for the clarification. I've got a hard drive that's slowly dying on my home computer, so maybe I will soon get the chance to perform a post-mortem.

Well, I haven't read the Kozierok, but this is the most lucidly materialist explanation of this particular (popularly mystified) component I've ever read. Nice work, Matt.

If files that are deleted remain on the hard drive doesn't it fill up? When you check properties to see how much memory is left on the HD there is a pie chart showing used and available portions. As the disk fills up with the deleted files (assuming you saved an awful lot of them!) is this reflected in the piecharts used section? And, finally, is there anywhere where you can look to see how much memory the deleted files are taking up?

Hi Andy,

Good questions. The files remain on the drive, but they are re-allocated as "free" space and are gradually overwritten as more data is saved. There are, however, a variety of techniques for recovering and restoring files even after they have been overwritten, though the effectiveness of such techniques diminishes over time. Check out Norton Utilities for a basic starting point.

I talked to someone the other night about whether the deleted files eventually got overwritten, and she said they did. Of course, it would be interesting to know at what point they were overwritten: i.e. whether it was when the HD was nearly full or whether it was to do with the fragmented state of the drive.
I find watching the defragmentation process quite therapeutic as the various pieces of files get moved about and larger spaces are created. In itself the thought that a file might be split up into various pieces and slotted into spaces all over the computer, but is magically "joined together" when you open it up again is facinating. Of course, it may be that although the file appears on the screen of all-of-a-piece, in reality it is still in pieces, so to speak: the bytes of the particular "length" of the bit stream in reality remaining separated. Although you may have a piece of text of a certain length, say 20 lines, which is a meaningful whole in cognitive terms, in reality it may be divided up on the hard-drive in a completely unmeaningful way, in the middle of sentences and words, even.
Sorry, getting carried away here.