What is an SSD? – Solid-State Drive Definition


Solid-state drives (SSDs) are a type of storage device that store data on memory chips, as opposed to traditional hard disk drives (HDDs), which use spinning disks.

SSDs are also known as solid-state disks and electronic disks.

SSDs are made up of non-volatile flash memory chips. Unlike volatile RAM (random access memory), they do not require power to retain data, unlike volatile RAM (random access memory), which requires constant power.

Because SSDs don’t have any moving parts and therefore aren’t subject to physical wear. They are generally more durable than HDDs.


If you’re thinking about buying a laptop (or have just bought one), you may be wondering what the difference is between SSD and HDD.

SSDs are faster and more reliable than HDDs. But they also tend to be more expensive, so an HDD may be a better option if you want to save some money.

This article will explain what SSDs and HDDs are and why you should think about buying one. It’ll also tell you what the pros and cons of each device are so that you can decide which one is right for your needs.

Types of SSD

Types of SSD

As you’ve probably noticed, there are many types of SSDs. Here’s a brief overview of the most common ones:

SATA SSDs connect to motherboards via the Serial ATA computer bus interface. This connection is restricted to SATA speeds (i.e., not much faster than a standard hard disk drive).

NVMe SSDs, also referred to as PCIe SSDs and M.2 SSDs, connect directly to the PCI Express bus through an M.2 slot on the motherboard or a PCI Express adapter card.

These are typically faster than other drives, with read/write speeds ranging from about 500 MB/second for low-end models up to 5 GB/second for high-end models using multiple buses in parallel.

Advantages of SSD

What sets SSDs apart from HDDs, however, is performance. The simple fact is that SSDs are just faster than HDDs.

  • They read and write data more quickly.
  • They don’t have to spin up to a speed before they can be accessed (all of the data on an SSD is accessible almost instantly).
  • This means computers boot up significantly faster with SSDs than HDDs (around 30 seconds or less versus 60 or more).
  • Applications open quicker, as well.

SSDs use less power and are ideal for laptops or other mobile devices.

You’ll see them in almost every new laptop model these days—they’re preferred over HDDs for mobile computing because of their long battery life and cooler operation (less heat output equals slower battery drain).

In addition, SSDs run silently and shake much less than HDDs do because there are no moving parts within the drive itself.

This means that your computer will run cooler with an SSD installed, which is another reason they’re favored over HDDs in laptops and tablets. This also makes them a better choice for gaming machines.

The fans have a hard time keeping up with all of those hot-running components generating heat inside the case.

Disadvantages of SSD

SSDs are not a magic bullet, though. They have some disadvantages too:

SSDs are more expensive than HDDs per gigabyte of storage. In the past, you could get a 1 TB HDD for around $50, while an SSD with the same amount of storage costs $500 or more.

Things are getting better now, and prices are going down, but at writing this article, a terabyte-sized SSD still costs about 2-4 times as much ($100-$200).

Many SSDs have less storage space than hard drives (1 TB vs. 4+ TB).

Even though you can write to an SSD many times over its lifetime, you can still limit how often you can do it before it becomes unreliable and unusable. This is caused by something called memory wear.

It’s not such big of a problem nowadays since modern solid-state drives use sophisticated techniques such as wear leveling to prevent any single block from being written too often.

While hard disks may be magnetic and fragile in their own right, and they don’t like heat or physical shock, they can generally take more abuse than an SSD before failing.

For example, if you drop your laptop on the floor while it’s running, then there’s pretty much no chance that your solid-state drive will survive that fall unscathed like an HDD might be able to.

There is software available that can recover data from failed drives, but it is expensive.

It doesn’t always work perfectly, so some data might get lost forever even if you somehow manage to revive your drive.


An SSD is a type of storage device that uses solid-state memory to store data. SSDs are faster, use less power, and are more reliable than HDDs. However, they are also more expensive.

Now you better understand what SSD is and how they differ from HDDs.

Further Reading