Hard drive, what is it? What is a hard drive and how does it work? Pros and cons of HDD versus SSD.
HDD ("winchester", hdd, hard disc drive - eng.) - an information storage device based on magnetic plates and the effect of magnetism.
Applies everywhere in personal computers, laptops, servers and so on.
Hard disk device. How a hard drive works.
In the floor sealed the block contains double-sided plates, with applied on them magnetic layer planted on motor shaft and rotating at a speed of 5400 revolutions per minute. The block is not completely sealed, but most importantly, it does not let through small particles and does not allow humidity fluctuations. All this adversely affects the life and quality of the hard drive.
In modern hard drives, the shaft is used. This gives less noise during operation, significantly increases durability and reduces the chance of jamming the shaft due to collapsed.
Reading and writing is done with head block.
In working order, heads soar above the disk surface at a distance ~10nm. They are aerodynamic and rise above the disk surface due to updraft from the rotating plate. Magnetic heads can be located on both sides plates, if magnetic layers are deposited on each side of the magnetic disk.
The connected head unit has fixed position, that is, the heads move all together.
All heads are controlled by a special drive unit based on electromagnetism.
Neodymium magnet creates a magnetic field, in which the head unit can move with a high reaction speed under the influence of current. This is the best and fastest way to move the block of heads, but once the block of heads was moved mechanically, with the help of gears.
When the disc is turned off, to prevent the heads from sinking onto the disc and damaged him, they clean up in head parking area(parking zone, parking zone).
It also allows you to transport offline hard drives without any special restrictions. In the off state, the disk can withstand heavy loads and not be damaged. In the on state, even a small push at a certain angle can destroy the magnetic layer of the platter or damage the heads when touching the disk.
In addition to the sealed part, modern hard drives have an outer control board. Once upon a time, all control boards were inserted into the computer motherboard in expansion slots. It was not convenient in terms of versatility and capabilities. With hard drives these days, all the drive electronics and interfaces are located on a small circuit board at the bottom of the hard drive. Thanks to this, it is possible to configure each disk for certain parameters that are beneficial from the point of view of its structure, giving it a gain in speed, or quieter operation, for example.
To connect the interface and power, standard common connectors are used / and Molex/Power SATA.
Peculiarities.
Hard drives are the most capacious custodians of information and regarding reliable. The volume of disks is constantly growing, but recently this is due to some complexities and for further expansion of the volume, new technologies are required. We can say that hard drives have practically gone straight in achieving maximum capabilities. The spread of hard drives was mainly facilitated by the ratio pricevolume. In most cases, a gigabyte of disk space costs less than 2.5 rubles.
Pros and cons of hard drives vs.
Before the advent of solid state SSD(solid state drive) - drives, hard drives had no competitors. Now hard drives have a direction to aim for.
Cons of hard drives(hard drive)(ssd) drives:
- low sequential read speed
- low access speed
- slow reading speed
- slightly slower write speed
- vibrations and slight noise during operation
Although on the other hand, hard drives have other more weighty the benefits to which SSD accumulators strive and strive.
pros hard drives (hard drive) compared to solid state (ssd) drives:
- significantly better volume price
- the best indicator of reliability
- higher maximum volume
- in case of failure, many times more chance to recover data
- the best option for use in media centers, due to its compactness and large capacity 2.5 drives
About what worth paying attention when choosing a hard drive, you can see in our article "". If you need hard drive repair or data recovery, you can refer to.
