A hard disk drive is an electromagnetic data storage device and it is the main storage device on a computer. It consists of one or more platter, each of which has at least two magnetic heads. The platters rotate with the help of a spindle motor. The magnetic plates are usually made of glass or aluminum and coated with a thin layer of magnetic material. The whole body is tightly sealed to prevent dust from entering the mechanism.
The Origin
Originally hard drives were very big and expensive too. Because of their size, hard drives were not suitable to be used when data needed to be transported. Earlier, hard disks could only be used in a protected environment and required a large amount of space. Also their large size implied more power consumption. However, we have come a long way from that. Today hard disks have a storage capacity that ranges from 160 GB to 1 TB of data and having a speed of 7200rpm to 10000rpm. As a result they are now seen not only in computers, but also in other electronic gadgets.
Many mobile phones and i-pods today use mini hard drives to store data. It is not like the hard drive has never had any real competitor. Today we have what is known as NAND flash drives. Instead of magnetic plates, these drives use semiconductor chips. This reduces the number of moving parts in a disk drive, makes it more durable and in turn reduces the amount of power required to run.
Competition
However, these flash drives are almost one and a half times the cost of a hard drive of the same capacity. While flash drives are compact and can be used to carry data around in your pocket, it is not very likely that they can actually replace hard drives.
For one thing, hard drives have been with us for over 50 years and have shown a phenomenal growth rate over these years. In addition to that, hard drive costs have decreased dramatically alongside increases in storage capacity and access speeds. Hard disks are available for as low as $0.20 per gigabyte. They are also extremely reliable. Hard drives are tested internally before being released in the market, thus ensuring that the error rate remains as low as 1bit per one billion reads. This is very important in areas like defense, banking etc.
Flash drives have been touted as being more durable when compared to hard drives. The plastic or metal casing on these flash drives ensures that the internal semiconductor chips are not damaged under any circumstances. However, today even hard drives have more safety features. For example there are ‘free fall’ sensors on a hard drive, which can detect if the drive is about to hit some hard surface. It will then move the head to a safe place on the drive and thus ensures minimum damage.
Nowadays, hard drives are used in a lot of things from cars to mobile phones, which means that the durability of these drives has been improved dramatically. From being used only in protected environments, today’s hard disks can withhold fairly high amounts of vibration, heat, cold or shock and come out unscathed.
Will It Survive?
In spite of all these advantages, it cannot be denied that flash drives do have advantages over hard drives. That is why hard drive manufacturers like Seagate have compromised by building hybrid drives, that is, hard drives with flash memories. These combine the flash drive’s low power consumption and faster access speeds along with the hard drive’s cost effectiveness.
Taking all advantages into consideration, it seems that the market is dominated by hard disk drives for storage, at least for now. Flash drives seem to be catching up fast, but still are too expensive to be used widely. More and more improvements are now being made on the hard disk drives, making it more and more effective, compact and yet inexpensive. Flash drives are also being used and are on the rise in the market. Currently, hard disks rule the storage devices market but flash drives could become less expensive with time, making it more affordable for everybody in the long run.
Computer forensics (or digital forensics) experts analyse systems and identify evidence of criminal activity and data theft or mis-use.