What is a hard drive?

A hard drive is an electro-mechanical storage device for your computer.


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When shopping for a computer and comparing specs, you might ask: What is a hard drive and what does it do? Short for hard disk drive (HDD), a hard drive is an electro-mechanical storage device for your computer. All your digital data can be stored in and retrieved from this device, from your images, music, and videos to your documents, applications, and video games.

Types of hard drives

There are two types of HDDs: internal and external. Internal ones are typically faster and cheaper per gigabyte. The internal variety can also offer more security and stability because they usually remain still and are harder to misplace. On the other hand, external hard drives are convenient to use because of their portable nature. Though, with the proper hardware, you can convert an internal hard drive to an external one.

Why are they called hard drives?

HDDs have been around since the 1950s. Initially, they were called Winchester drives or fixed disks. Later the name evolved to hard disk drives to differentiate them from floppy disks, which are usually made of very flexible plastic.  

Why aren’t hard drives silent?

Unlike other storage devices such as RAM (random access memory), an HDD isn’t always silent when working because its operation is mechanical. A hard drive can use magnetic storage, rotating platters, and an actuator arm to read and write information. The rotating platters are magnetized disks that spin at speeds of 5,400 RPM and upwards. The greater the RPM, the faster the drive.   

How big is a hard drive?

HDDs generally come in two physical sizes: 3.5” hard drives, which fit inside desktop computers, and 2.5” hard drives, which fit inside portable devices like laptops or external drives. 3.50-inch drives typically have higher data transfer speed than 2.5” ones because they usually spin faster. While fast 2.5” hard drives do exist, they’re fairly pricey, at least for now.

In terms of storage capacity, the biggest consumer HDD is 20TB as of late 2020. However, you can expect hard drives to become larger and cheaper per gigabyte as the years progress. After all, the average hard drive has gone from MBs to TBs in just a few decades.  

Do all computers have a hard drive?

All computers need internal storage to hold their operating systems, data files, and critical programs. But not all computers use a hard drive as their storage drive. For example, Chromebooks don’t have hard drives. Instead, they use internal flash storage. If you want to add more storage to your computer, adding an external hard drive is one way to do so.


Is a Solid-State Drive (SSD) a hard drive?

Computer users often use the word “hard drive” or “hard disk” as an umbrella term for any storage device, similar to how many people incorrectly use the term ‘computer virus’ for any malware. You can learn the difference between virus and malware by visiting our blogs. But let’s get back to storage drives.

As mentioned earlier, the term hard drive is short for a hard disk drive, and an SSD (solid-state drive) is not a hard disk drive. SSDs store data on interconnected flash-memory chips, similar to but not the same as memory cards and flash drives. Unlike a hard disk drive, there are no magnets or moving parts in an SSD.

Is a Solid-State Drive better?

Like many computer users, you may be wondering: is SSD better than HDD? The answer depends on your needs. SSDs are increasing in popularity because they’re more reliable and significantly faster than HDDs. Studies have shown SSDs to have a much lower failure rate than HDDs. However, hard disk drives are far more cost-effective per gigabyte, at least today.

What hard drive should I get?

If you’re purchasing a hard drive, you may want to get the fastest and biggest one you can afford. You’ll want to be sure the hard drive is compatible with your computer, whether you’re adding an internal or external one. To reiterate, a 3.5” should work for your desktop while a 2.5” will work with your laptop.

Also keep in mind that modern hard drives usually use SATA connections while older ones use the slower IDE interface. Your computer likely has SATA ports. But you can still connect a SATA drive to a legacy IDE port on an ageing computer with the correct adapter.

How do I secure my hard drive?

Computer security includes keeping your hard drive safe. Best practices for computer (including hard drive) safety include:

  • Set a strong login password to prevent others from easily breaking into your computer. You can also use biometric technology like fingerprinting and face recognition to secure your machine further.
  • Use a device locator app to keep track of your computer and its internal storage drive if you misplace it.
  • Avoid accepting gifts like keyboards or flash drives from untrustworthy parties. They may carry an integrated keylogger.
  • Learn how to encrypt files and folders to protect your information. With the right tools, you can even encrypt your entire hard drive.
  • With anti-malware software, you can shield your hard drive from viruses, ransomware, and other malware.

Even the best cybersecurity tools can’t make your hard drive impregnable to security risks. You should consider backing up your data to reliable file-sharing and cloud storage sites regularly.

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