What is the HDD (Hard Disk)? What does it do? What are their types and differences?
You need the information and downloads to use your computer. This information is kept in a storage device called an HDD. We have prepared a comprehensive article about HDD. What is HDD (Hard Disk) in this article? What does HDD (Hard Disk) do? What are the HDD operating principles? What are the HDD (Hard Disk) types? What to consider when buying HDD (Hard Disk)? How Hard Disk Works? What is the Latest Hard Disk Technology HARM? What is an SSD? What are the differences between HDD and SSD? What are the advantages of using an SSD disk? We will convey the answers to your questions.
The storage unit used to permanently store our data on the computer is called HDD (Hard Disk). The device called hard disk; it consists of several parts lined up on a rotating shaft. These; plates made of plastic or metal and covered with the magnetic layer are formed by the read/write heads on the upper and lower parts of the plates. Any data you have recorded on the computer; is recorded on the magnetic layers on the disc. While recording the data on the hard disk, the magnetization logic is acted on. The two poles on the magnet correspond to the values 0 and 1. In other words, the data you have recorded is recorded on magnetic media. There are also circular lines on the magnetic layers. The name of these lines is also called a track.
On an HDD; multiple plates are stacked on top of each other. Data is written on the top and bottom of the plates. A face on the HDD can be read by ahead. As such, the face and head become the same definition. The part in the smallest area on an HDD that is addressable is called a sector. However, the longest amount of data that the industry holds on can be 512 bytes long. The head and trace on the HDD are used to address the data to be written.
How Hard Disk Works? How Does The Working Principle Work?
Looking at the foundation of HDDs, it is seen that they all have the same structure. It consists of a whole HDD and the following parts. First, they have one or more plates that are stored, the second one has literacy heads. Then some engines have the task of providing the movement between reading and writing heads and plates. Finally, there is a control card that is responsible for the control on the HDD, that is, it holds its circuits. Today, classic desktop computers can be purchased with an HDD between 300 GB and 1 TB. The data loaded on the HDDs are stored as the smallest storage package called byte.
It is important to give the following information here. Those who are closely related to the computer world know that; 1 byte consists of 8 bits. When looked like this, you can call it the smallest unit bit. However, 1 bit does not make any sense in terms of storage. Every data written on the HDD is packed in bytes. Let's take a look at how it works with the parts in the HDD.
What are the Features that Determine Hard Disk Performance and Capacity?
When buying a hard disk, there are 3 main features to look at in order to comment. These; the rotational speed of the plates, data transfer speeds, and access times. Let's say this; capacity on a hard disk; The number of plates and the data density on the plates determine.
Rotational Speed: The rotational speed of the plates on the hard disk. Nowadays, it is like there is no disk with IDE connection. However, in IDE disks; the number of turns was known as 5400 and 7200 RPM. The expansion of the concept of RPM is Rotates Per Second, the rotational speed per minute. However, this rate of rotation is 15,000 RPM in SCSI disks.
Access Time: It is the name given to the elapsed time that the reading and writing head on the disk reaches any point. Access times; On average, it is 10 ms on IDE disks and less on SCSI disks.
Data Transfer Speed: The name was given to the amount of data that a hard disk transfers in one second. It may vary depending on the characteristics of the disc being used and the interface of the disc.
What is an Interface?
The interfaces on desktop computers that we are accustomed to seeing are the IDE and SCSI types that we come across on the server-side. The IDE connection type is by no means a standard. Rather, it relates to the control of the data flow between the processor and the HDD. However, with the parallel ATA system developed by IBM, a universal standard has been created for communication between the computer and the HDD. The reason for the IDE's removal from the interfaces was its compatibility and price. For this reason, it became a very common system for desktop computers in time. However, today it has been replaced by parallel ATA interface technology to serial ATA technology.
The difference in the Serial ATA interface is; This is because the data transmission is done in series, not in parallel. If we list it in advantages; serial ATA consumes much less energy and has fewer pins. It also has a much thinner connecting cable. The third advantage is; much more advanced fault finding and correction.
Let's get to the SCSI interface. This type of interface; is mostly used for professional applications. It is especially used in workstations or server systems. However, it costs a lot compared to IDE interfaces. The biggest advantage of the SCSI interface is that it works asynchronously. So as on IDE disks; Although SCSI drives are connected to the same controller; they do not compromise on their own performance and data transfer speeds. SCSI interfaces; They have a card called SCSI Host Adapter. This allows us to organize data transfer and to have a separate processor and memory. For this reason, SCSI devices place much less load on the system than IDE devices.
To illustrate as follows; With a parallel ATA, you can connect only two devices to one channel. However, when it comes to the SCSI interface; It is possible to connect up to 15 devices at the beginning of the channel. And if we consider the servers of a large structure; has become a very necessary need. The biggest feature of SCSI disks is that they are much longer-lasting than IDE disks. Because it is produced for trouble-free operation. For example; It is very important that the system does not stop when performing continuous and heavy operations such as video mounting. In such cases, it is absolutely essential to use SCSI disks for the system to continue. The performance of SCSI drives is extremely smooth.
What Should Be Considered When Buying Hard Disks?
First of all, the first thing to look for when buying a hard disk; it should definitely have storage capacity. You should look at how much storage space you need and decide accordingly. Secondly, for a fast data flow, you should look at the rotation speed. The third thing to look at is; The number of sectors per track should be checked. The fourth important feature you should look at is; access time of the hard disk. In the fifth part, internal data transfer should be considered. Finally, the connection types, namely the interface used on the hard disk, should be selected.
What are the Considerations When Using a Hard Disk?
The most important issue to be considered when using a hard disk; is the problem in the assembly part. It should be mounted on the lowest place in the case. While making the connection; The red ends of the connection ends should be mounted facing each other. You should divide your hard disk into at least two parts in case there is a problem with the operating system. The hard disk should not be moved in any way. It should definitely be protected from possible impacts. The screws should never be left loose after assembly. In old type IDE disks, it should be ensured that jumper settings are made.
What is the Latest Hard Disk Technology HARM?
Hard disk manufacturers; he is especially working to open the way for hard drives. The most important step among these studies is; is to keep up with new technologies. SSDs currently on the market appear to be state of the art products. The reason for this is that Hard disks will reach the capacity limit in a while. So what will HDD manufacturers do when this happens? Production will of course not be canceled. However, according to the Seagate company statement, there are 2 roads in front of them. The first way is a new media mold technology or heat-directed magnetic recording technology. So new technology called HARM. The reason for HARM technology being more advantageous; it allows data to be written much closer together. To be honest; We can easily see 200 to 300 TB hard disks in the market with HARM technology between 2020 and 2025. As a result, it doesn't seem like a very smart idea for hard drives to come out of our lives.
What is SSD?
Unfolding of SSD disks; Responds with Solid State Drive. In Turkish version; Refers to solid-state drive. The biggest advantage of SSDs is that they are designed to be moved. In other words, it does not contain any mechanical parts. Unlike SSD disks; It consists of internal circuit and memory chips. For this reason, there is no head mechanism. And its durability takes much longer. Today, a good desktop or notebook computer has become absolutely essential. SSD disks; they have very high literacy rates. Therefore, they work at least 2 times more performance than a normal IDE disk.
What are the differences between HDD and SSD?
As we mentioned above, HDD disks store data on rotating disks. SSD drives are therefore advantageous. Because they do not have a moving mechanism. So SSD drives are in a sense similar to USB sticks. But SSD; It does the same job with the HDD. So expected from a hard disk; Installing your operating system provides access to your personal applications and files.
What are the advantages of using an SSD disk?
It is the largest and definitely visible speed of SSD disks compared to HDDs. Compared to HDDs, it is seen that applications on computers with SSD disks, even computers, are opened much faster. Therefore, you have used it on computers; The difference of SSD disks emerges in all uses of games, business applications, or educational applications.
SSD drives have no moving parts. For this reason, sudden breakdown situations like HDDs are very rare. However, recovering data from a failed SSD disk can also be quite difficult. Because SSD disks have a certain write capacity. Therefore, it becomes unusable when its writing capacities are full. Of course; can serve for years in personal and normal use. They are not affected by any external shaking like HDDs.
A common feature in HDD disks; the sound coming from disk and engine. In SSD disks, there is no sound at all. They work extremely quietly. SSDs do not fragment as they are on HDD disks. On the contrary, if this problem occurs, they have a mechanism that will automatically fix the problem. Therefore, there is no need for any extra intervention.
Finally, SSD drives are so great, but they also have a number of disadvantages. It is also a cost. SSD disks are considerably more expensive than HDD disks. The disk, which has 500 GB of storage space on HDD disks, is known as an input model. However, the storage space of the entry-level model of SSD disks is known as 128 GB. Because of this, a large HDD can be used. However, if it has a small SSD on it. Today, the operating system and important applications are installed on the SSD, and both speed and cost savings are achieved.