How does a hard drive work?

Question

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How does a hard drive work?

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Answer 1

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I have always been struck by how a hard disk of a PC works due to the noise they usually make when they are active (reading / storing information) . A hard disk is a hardware device that is responsible for storing data so that it can be accessed at any time.

Hard drives are also designated with the letters HD (Hard Disk) or we can also see them as HDD (Hard Disk Drive) .

How does a hard drive work?

Without going into great technical details, we could say that a hard disk uses an electromagnetic system to write or read information on turntables. First of all, we must know the different parts that make up the hard drive and what is its function:

• Dishes : they are disks that spin at high speed and are on top of each other. The material from which they are made may vary, but the most common are those of aluminum or glass. Each plate has two faces on which data can be stored. The rotation of the plates is achieved using a small electric motor.
• Head : are responsible for processing electromagnetic impulses to retrieve information or store it. The heads are placed on the plates, more specifically there will be a head for each side of the plate. These heads never touch the surface of the plates, but they are located at very small distances.
• Arm : so that the heads can move over the entire surface of the plates they need a mechanical element called an arm.
• Printed circuit : is responsible for processing the different orders to control the disk.

The hard disk communicates with the PC through one of the available standards (IDE, SCSI, SATA, etc.) being the most current SATA that allows transfers of up to 6 Gb / s.

Hard drives also refer to the speed of rotation, more commonly referred to as rpm (revolutions per minute). As of today, 7200 rpm is the most common rotation speed on hard drives.

For more details of the operation of the hard disk I recommend the following very illustrative video:

Finally, it should be clear that this article talks about hard drives and not SSDs, which have recently broken into the market and employ a different technology.

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