Hard drives or hard disk drives are a core component of any computer or computer system. By definition, a hard drive is a computer device that keeps software and data contained within a computer. Hard drives provide a permanent store of data which is non-volatile. When power is turned off, the data contained within a hard drive is retained (not lost). When accessing data on a hard drive, the process is akin to random, non-sequential access. In this article we shall be looking at the different types of hard drives.

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Basic Uses Of Hard Drives

Hard drives are used for a wide range of things. The primary use is for the storage and installation of the operating system of a computer. Every computer has applications that are used for used for different purposes e.g. Microsoft Word. These are also stored in and installed in and through the hard drive. They are also used for general data storage i.e. you can store your documents in the hard drive.


Parallel Advanced Technology Attachment – PATA

These hard drive types are the pioneers when it comes to hard drives. They came onto the scene around the mid-eighties. They were characterised by data transmission rates of as much as 133 megabytes per second. One drive channel could accommodate two devices. These types of hard drives were also known as integrated (or enhanced integrated) drive electronics (IDE or EIDE).

Motherboards could accommodate 2 channels meaning that a total of 4 hard drives could be attached. They were made of several moving parts inside – thus they were liable to physical damage. Their working principle of storing data was through magnetic fields. Data transfer would be done parallel and in a simultaneous manner. This would be done through a series of wire ribbon cables.


Small Computer System Interface – SCSI

Earlier we talked about the IDE hard drives – as in, the PATA hard drives. The SCSI hard drive type is more or less the same as the IDE hard drives. The SCSI came onto the scene around the 1970s period. They could facilitate as many as 15 devices to be connected to one motherboard. The key difference is that they use an interface called the Small Computer System Interface. Connections here can be done internally or externally. This hard drive type is fast, can operate round the clock and is easily scalable in arrays.

When it comes to the storage and transfer of huge amounts of data, SCSI hard drives are most suited. By the way, just like PATA and SATA, the SCSI is comprised of moving parts inside. SCSI hard drives have data transfer rates of up to 80 megabytes per second. There are so many different types of SCSI hard drives that have been developed over the years. This presents a huge challenge in getting to choose the appropriate cable for your needs.


Serial Advanced Technology Attachment – SATA

This came to somewhat replace the PATA. In principle, the SATA and PATA operate on the same basic framework. They differ significantly in terms of their interfaces. SATA hard drives are much faster in terms of data transfer because they do so using serial signals. The cabling used for SATA hard drive type is much thinner and easier to handle. Their data connection protocol is 7 pin plus a SATA hard drive’s cable is confined to just one metre. Their power consumption is also way less. There is no sharing of bandwidth due to the fact that only 1 hard drive can be accommodated on the motherboard. Once the SATA stepped onto the scene, the PATA literally went out of use.

One of the biggest reasons for why SATA hard drives are in common use is their widespread support framework. Virtually any motherboard or operating system is compatible with SATA hard drives. Not only are they used for computers by they are also commonly used for gaming applications. PATA data transfer rates reached high as 133 megabytes per second. SATA hard drives came to exceed that to reach top data transfer rates of 600 megabytes per second. Do not forget that the use of magnetic fields was still employed for SATA so as much as that data transfer rate was good it could not be enhanced further.


Solid State Drive – SSD

This is the best type of hard drive. The foremost attribute of solid state drives is that they do not have moving parts. They are the most recent innovation when it comes to hard drives. In terms of how they store data they do not use magnetic fields. The technology that solid state drives are built on is called flash memory. Flash memory employs the use of semi-conductors or integrated circuits. To understand flash memory, just think of how the RAM on motherboards works. This working mechanism makes it possible to store data permanently – though of course it can be deleted when needs be.

The advantages of solid state drives are many. Obviously it is faster to access data and liability to physical damage is eliminated since there are no moving parts. They also consume low power. Solid state drives are also very durable – they can last up to over 2 million hours of use. The most significant hurdle of SSDs is the cost factor; this type of hard drive is costly.


Considerations To Make When Choosing Hard Drives

There are basically 3 considerations you can make when looking to settle for a particular hard drive type. These considerations are storage capacity, overall performance and a holistic package. SATA hard drives are the perfect fit for high storage amounts. Then if you are looking for the best performance and an all-round convenience the SSD is the best pick. In fact, SSDs are now the best pick when it comes to hard drives in general. Solid state drives are still an expensive type of hard drive, as we highlighted earlier. However, due to their superior benefits they are wired to become widely adopted in due course. Technologies often start out expensive by over time the cost falls gradually.