what is hard disk

 

 

What is  hard disk?

what is hard disk

Hard drives both desktop and laptop hard drives simply put work all if your data is stored now this is different from memory if someone asked how much memory you have talking about RAM a random access memory which is a different component .

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There are several different types of hard drives out there but the first we're going to look at is their this I D Drive which stands for integrated drive electronics legacy that has pens for the ID cable in for the ID power as well I D E is older technology which is reflected in axis peace there’s also a jumper which is a little plastic piece that allows for cable select are deciding they will be a slave our master for cable select work and I D Drive must have missed jumper set CS and the using a cable that supports it for jumper settings .

 what is hard disk in computer

You can look at the label and to chase a jumper it's as simple as pulling it off placing it on the appropriate pins say two stands for serial advanced technology attachment say there is a newer technology is much faster than the older I'D drives the say to drive doesn't have pins like the ides there's a way to power connection an essay to data connection there is a spot for a jumper which typically won't see that going to say to drive the standard size for both types of hard drives is about six inches by 4 inches .

 

Which for obvious reasons not fit into laptop these are made for desktops only in with the desktop you're able to put multiple drives within the computer for multiple hard drives for both I D And say to you need a cable for each drive that connects to the motherboard as well as a power cable freeze-dried the power cable comes from the power supply in the data connects to the board on a board that has say the connections you can put up to six drives you have space available.

 hard disk definition and function

what is hard disk

Now an even newer technology is a solid state drive these are even faster than the Seder drives but they cost a lot more too which leads to say the driver still the most commonly used and as far as the ID you'll find too many those anymore now laptop hard drives are very similar but there are a few differences.

 

Besides the obvious contrast size for the ID knows there's only one strip of pens but and there isn't a power cable rather than using cables the drive a plug directly into the IDport which is built into the motherboard supplying both power and data and on some laptop drives there will be a small plastic tab to help pull it out taking a look at say two drives for a laptop .

 

 you can see that the connections are the exact same as for the desktop this makes a universal and the sense that you can now laptop drive in a desktop computer if you have the proper amount the label tells us all the important information about the drive and something's not all of us really need to know some of the important information that must be  included in the manufacturer jumper information of the speed and the storage capacity .

 

what's on this when we can see is a 160gigabytes storage capacity is simply the amount of data you drive can hold hard drives can have a wide range of sizes but typically these days and the hundreds of gigabytes sometimes even into the terabytes with external hard drives are mass storage devices the speed of a hard drive is measured by rpm this drive here is rated at 7200 rpm this means that the disk spins around 7,000 two hundred times in one minute or 120 times per second  .

 

what is hard disk

The discs  the faster it is able to access data for example if you need to access a document which is stored here the faster it spins means the faster overreached are in the red listed with the speed is usually a cash the cash is a small amount of memory and the drive circuitry in a sort of a buffer between the computers and hard drives  .

 

Now we've covered the basics let's take closer look inside of one now and check out what parts make up the hard drive the first component to look at will be the controller card a lot of times ever drive is not working a simple troubleshooting step is to replace the card with an identical one from another good drive if you have one available then this can be easily  and simply  fixed  to a hard drive problem here we can have a hard drive with the controller card  taken off the back to open up the hard drive you need to remove all the torch Koran .

 

There will  be   a screw hidden under the label now  and inside this there will be  control arm which reads the drive by scanning back and forth this is somewhat similar to how record player works except that reads from the inside out things such as our operating system and other programs that come installed on the computer and it will be so  closer to the center and then it will  start work.

Its way out thing sat it later such as documents are other programs will be stored further out on this the disc is also known as a flatter and are typically made of non-magnetic materials have an extremely thin coating paramagnetic material on top now we won't get into details  but the platter is separated into tracks and sectors tracks are concentric circles and sectors or wedge-shaped this helps with the organization and filing at the data is stored in these magnetic fields in a digital format as ones and zeros now .

 

What is the use of a hard disk?

 

How to use external hard drives. Now most of the external hard drives  will come with what is called a USB connector which will  look similar to this, and  it has got a little square connection here. Many  computers have several USB ports available .

what is hard disk

 

 We are going to plug my external hard drive into the USB port in my laptop. Now if we go to look at  the computer, you will be able to  see that it is   immediately as we  plugged it in, it opened up that external hard drive on my computer. And there's no data on there right now. We are going to kind of minimize this a little bit where I can, where we can copy some data to it.

 Let's say that  we want to move that  portfolio file to our external hard drive. If we Just right click on it, then we're going to say  copy and then inside of the  external hard drive where it will be  empty, and then right click in that area and just say paste. Now  it  has  copied this portfolio file into my external hard drive.

 

But you've made a copy of it on another media. So if this computer knows where to  stop working or the hard drive dies or something like that,  we still have a good backup copy over here on my external hard drive that we can simply   just unplug and store in a drawer somewhere and I've just shown you how to use an external hard drive.

 

• what is hard drive

The hard drive has been the main storage device in computers for decades now. Do you ever wonder what's on the inside? Hard drives are sealed so that no dust can get inside, once you take yours apart it most likely will not work anymore. The platters is where the information is stored. Both the top and the bottom of each platter is used so it can store as much information as possible

Types of hard disk

Basically the hard disk has been divided into two parts

1.     SSD (secondary storage device)

2.   HDD(Hard disk drive)

 

HDD vs. SSD

 

We will start comparing  these two drives in terms of their speed and the performance.

 Now, the technology of hard disk drives has been  improved tremendously  over the past  two decades. And the data density of this drive has  been increased tremendously. But the speed of this  hard disk drive hasn't increased at the same pace.

Is SSD better than HDD

Typically,  the access time of today's hard drive is in the range of a few ms. And the sequential read or write speed will be  around 100 MBPS.

 If we  are thinking  about the speed of this  hard drive it  is not bad then you will  have the access time of RAM and the cache memory which will be  used in the computer and it will be in  the range of nanoseconds. Which will be significantly very  less than the access time of these hard drives.

So, even if we  have  a very high-end CPU and it is  coupled with a graphics card and RAM, still we  will not be able to extract the best performance out of that system and  if you are stuck with the slow hard disk drives.

what is hard disk

Typical sequential of  read and write speeds will be in the range of 400 to 500 MBPS. And in fact,  it will be  possible to achieve this  sequential read and write speed in the range of GigaBytes per second using these SSDs.

 

So, now we look into the internal structure of these drives and let's  try to find out why SSDs are fast as compared to  hard disk drives and why  hard disk drives  are relatively slow in comparison to these SSDs.

So, these platters  can rotate at the typical speed of 5400 or 7200 RPM in laptops. And it has the capacity  to  go up to 10000 RPM on desktop computers. And in some enterprise hard disks, the speed can reach  up to 15000 RPM.

 

what is hard disk

So, in these hard disk drives, the data can be  stored magnetically on  platters using the head. And typically the data will be stored in this hard disk drive in the form of tracks and the sectors. Now, as it involves the mechanically moving parts, there will be the  limitation on the speed at which the data can be accessed or written on  hard disk drives. On the other end, the SSDs are designed by  using the flash memory. And to be precise, they are designed using the NAND flash memory.

SSD not only contains flash memory but it also has the microcontroller and the small cache memory. So, using the microcontroller, the flash memory cells can be accessed or programmed. And using the cache memory it will be  possible to store the incoming and the outgoing data temporarily..

For desktop, it will be  available in 3.5-inch form factor, while for a laptop it will be available in 2.5-inch form factor. On the other end, the SSDs can be  available in many form factors.

The most common among all will be  2.5-inch form factor, where these drives can be used as well as replaced in place of hard disk drives. Apart from these, the mSATA and the M.2 SSDs are available in very small form factors. And they are used in Ultrabook's and tablets.

what is hard disk

A technique called the thin film lithography process allowed engineers to shrink the reader and writer. Bits could also be packed closer together thanks to mathematical algorithms that filter out noise from magnetic interference, and find the most likely bit sequences from each chunk of read-back signal.

 Thermal expansion control of the head, enabled by placing a heater under the magnetic writer, allowed it to fly less than five nanometers above the disc's surface, about the width of two strands of DNA.

For the past several decades, the exponential growth in computer storage capacity and processing power has followed a pattern known as Moore's Law, which, in 1975, predicted that information density would double every two years.

But at around 100 gigabits per square inch, shrinking the magnetic grains further cramming them closer together posed a new risk called the super paramagnetic effect.

When a magnetic grain volume is too small, its magnetization is easily disturbed by heat energy and can cause bits to switch unintentionally, leading to data loss.

Scientists resolved this limitation in a remarkably simple way: by changing the direction of recording from longitudinal to perpendicular, allowing areal density to approach one terabit per square inch. Recently, the potential limit has been increased yet again through heat assisted magnetic recording.

 

Conclusion

 

In this article we have provided you information on what is hard disk and hard drives and we also discussed SSD AND HDD and also we have provided information on which  is better  SSD or HDD.