HDD vs SSD: differences and advantages of both types of hard drive

HDD vs SSD: differences and advantages of both types of hard drive
7 min read
26 October 2022

We are going to explain what the differences are between HDD or SSD hard drives. For that, we are going to start by describing in a simple and easy to understand way what are the general features of hard drives, both mechanical or HDD and solid state or SSD. Thus, you will be able to learn to recognize and differentiate them without problems.

Then we are going to continue with a comparative table in which we are going to show you the main characteristics of both, and we will continue with an in-depth explanation of what these characteristics are and what they imply. Finally, we will end up telling you on what occasions it is recommended to use HDDs or SSDs, so that if you want to buy one you can have an informed decision.

Hard disk or HDD (Hard Drive Disk)

Hard drives, also known as HDDs, are a computer component used to permanently store your data. This means that the data is not deleted when the unit is turned off as it happens in the data stored by the RAM memory. The first company to commercialize them was IBM in 1956.

They are comprised of mechanical parts, which is the reason they are at times called mechanical hard drives, and they use attraction to record your information and documents. It is comprised of at least one unbending plates joined by a similar hub and turning at rapid inside a metal box. On every platter and on every one of its countenances, a read/compose head peruses or composes your information onto the circles.
The more slender the circles, the better the recording will be, and the quicker they turn, the quicker the information is communicated, both while perusing and composing. Normally, the speed of hard drives is typically 5400 or 7200 RPM (cycles each moment), albeit some server-based drives can go up to 15,000 RPM.
As far as size, mechanical hard drive fenced in areas can be 2.5" or 3.5". Its cost might change relying upon its size, however particularly on its capacity limit. Truth be told, the extraordinary benefit of these hard rolls over SSDs is that they are a lot less expensive.

Solid state drive or SSD

Solid state drives or SSDs (Solid State Drive) are an alternative to hard drives. The big difference is that while hard drives use mechanical components that move, SSDs store files on microchips with interconnected flash memories. Therefore, we could almost consider them as an evolution of USB sticks.

SSDs usually use NAND-based flash memories, which, as they are also non-volatile, keep the information stored when the disk is disconnected. They do not have physical heads to record the data, instead they include an integrated processor to perform operations related to reading and writing data.

These processors, called controllers, are what make the "decisions" about how to store, retrieve, cache, and clean data on the drive, and their efficiency is one of the factors that determine the overall speed of the drive. Additionally, by not relying on a physical component to spin, it also achieves a quieter drive than mechanical drives.

In terms of size, these drives are usually 2.5", and have an almost identical design to mechanical hard drives, which helps them fit into the same cases and slots where conventional hard drives are mounted in a computer.

In this table you can see the main differences between both storage technologies. The main difference has to do with maximum capacities and price. Keep in mind that SSDs are much more modern, so it is normal for their price to be significantly higher. Today, a 250 GB SSD can be worth the same as a 3 TB HDD.

As storage units without moving parts like their predecessors, SSDs have some notable advantages such as causing less noise and vibration. It should also be made clear that we cannot say that mechanical hard drives are not extremely noisy either, so it is not a very important difference.

The one that is a notable difference is that of speed. In our comparison between the two technologies, we saw how an SSD booted up an operating system in less than half the time of a 7,200 rpm HDD, and more than tripled its data read and write speeds. In our test we used an HDD that read and wrote data at 150 MB/s, and an SSD that read and wrote at 545 MB/s and 525 MB/s.

Obviously, these specific data writing and reading data always depend on the different models on the market. But in general, SSD hard drives are always much faster than mechanical ones. Hence its high price.

The great concern around SSDs has always been around their durability, especially because of the little that the first units to reach the market had. The useful life of solid state drives depends directly on the amount of data you are writing to it, since each cell in a bank of its flash memories can only be written a certain number of times.

A study by Tech Report concluded that a fairly standard SSD, specifically a Samsung 850 Pro, could last up to 2.4 Petabytes of written data, which is equivalent to 2457.6 Terabytes. Therefore, the duration of one of these disks depends on how long it takes to write and rewrite the hard disk until you reach that amount, which is surely more than the 3 to 5 years of guarantee that manufacturers usually offer.

One of the drawbacks of SSDs compared to HDDs in terms of durability is that they have a higher failure rate. Even so, this is improving generation by generation, and has other advantages such as better resistance to shock. Remember, HDDs have mechanical parts, so a blow could cause them to break or wear out sooner, shortening their useful life.

In any case, and to avoid surprises, both in SSDs and HDDs that can last around 10 years or more, it is best to regularly monitor the health of your hard drive. Here's a collection of tools you can do that with, so you know when you might be about to experience an error that puts your data at risk.

In case you have found a mistake in the text, please send a message to the author by selecting the mistake and pressing Ctrl-Enter.
wasim tariq 125
Joined: 2 years ago
Comments (0)

    No comments yet

You must be logged in to comment.

Sign In / Sign Up