Hard drives are fascinating devices, and it can certainly be said without hyperbole that they’ve vastly increased the quality of our lives over the last dozen or so years.
Despite the fact that most homes contain a number of hard drives, from computers, Tivos, Xboxes, iPods, and even some cameras, most people don’t know much about the devices or their technology. Here are some interesting facts about hard drives to help you better understand how they operate, improve, and even how they fail.
1. The size of the drive on the package isn’t the same as in your computer. This is because hard drive companies and operating systems use different parameters to find the size of a drive; therefore, a 30 gigabyte drive might show up in a computer as only 28 gigabytes.
2. Multiple drives can be set up to act as one. This is known as a RAID (Random Array of Inexpensive Disks) array , and many businesses will set up a RAID with multiple drives, even into the dozens. By adding in a parity, they can ensure that when one of the drives fails, they’re able to switch it out before the entire RAID array goes down.
RAIDs can be set up to house hundreds of terabytes of information, and are often faster and more reliable than single drives–at an ultimately smaller cost (though consumers will blanch a little when viewing a few RAID price tags).
3. The term “hard drive crash” has a literal meaning. The heads of a hard drive float at an almost infinitesimal distance above the platters which store the information, and when they become misaligned they can literally crash into the platters–causing a plethora of weird-and-bad sounds and possibly data damage in the process. The term “hard drive crash” is therefore in some cases extremely accurate, though many computer users just think of it as hyperbole.
4. A hard drive’s PCB (electronics board) is drive-specific. They’re actually programmed to be optimized with the drive they were built with, at the factory that made them; this means that they can’t be switched around, even if two boards are from the same model of drive. Many computer users have tried this when their hard drive’s power fails; more often than not, it ends up making their problems worse.
5. In theory, hard drives double in size every two years. This is due to Moore’s Law, which states that the number of transistors that can be inexpensively placed on an integrated circuit is doubling at that rate. Through advances in hard drive technology such as parallel recording and increased data density, hard drive manufacturers have steadily kept up with Moore’s Law, with current drives holding over 1 terabyte of information. There are new technologies that indicate the trend won’t slow down for several generations of new hard drives, possibly longer.