Technical Terms: Hard Disk Drive and SSD

Computers come with one of two types of internal storage, either a Hard Disk Drive or a Solid-State Drive, also called an SSD. Hard Drives are older and cheaper technology, but also slower. SSDs are newer, smaller, faster, but more expensive. You can also get Macs with a Fusion Drive, that is a hybrid of the two.
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Closed captioning for this video is available on YouTube: Technical Terms: Hard Disk Drive and SSD.

Today let's take a look at two terms that describe the type of storage in your Mac. The first term is Hard Disk Drive. The second is Solid State Drive. These are the two main types of technology that you can still purchase with desktop Macs today.

Hard Disk Drive is sometimes called just a hard drive or just the drive in your computer. The abbreviation is usually HDD but you don't hear it called a HDD that often. Usually people just say hard drive. Now it's a magnetic form of storage. So actually using, you know, little magnetic bits on a spinning disk to store and then be able to retrieve your files and other things that you put on the drive. It has been around for a long time. It's been used in computers since really the 60's and it''s still something you can configure say an iMac with today.

Of course they've improved a lot in speed and cost and also the amount of storage over the years. They're fairly inexpensive today. So like, for instance, if you were to buy an external drive or replace the drive inside your Mac usually you can do it for less than a hundred bucks. You can get a huge one, like a 4 terabyte drive, for under two hundred dollars, usually.

This is what they look like. Usually there's a cover on top of this. So the unit's got like a metal cover on top. But you can in there see there's the spinning disk and it looks like a record player. It's got, basically, a little read head in there that reads from the disk as it spins around. So it's mechanical. It actually moves inside the box.

Now Solid-State Drive is not usually called a solid state drive. Usually we just say SSD. It's kind of interesting that hard disk drives aren't really called HDDs that often. They're called hard drives. But solid state drives aren't called solid state drives very often. They're called SSDs. The abbreviation has kind of stuck. Sometimes people called them Flash Drives because technically they're using flash memory or a type of flash memory. But most of the time when people say flash drive they're referring to the little thumb drives that you plug in not the actual, you know, internal drive or a large external drive. People usually just call these SSD's.

Now, SSD's don't have any moving parts. There's no spinning disk or anything in there. So they're not mechanical. They're basically using memory as storage. Now not usually the same type of memory that you've got in the rest of your computer. Usually they're super fast, super expensive memory used as memory and it's cheaper memory, maybe not quite as fast, used for storage as an SSD. Of course it's still so much faster than reading from a mechanical disk.

They haven't been around that long. Really you can only get them mainly as options or upgrade options in computers for the last ten years or so. They're fairly expensive. It still costs more per byte to store things on an SSD than it does on a hard drive. But prices have gone down quite a bit. This is what they look like. Now they don't have to look like this because they can be really any shape. Devices like say an iPhone or an iPad or something like that kind of fit them into the case. But if you're putting them in a computer the general idea is to make them the same shape as a hard disk drive so you can kind of have configurability there. You can configure the same machine with a hard drive or SSD. The drive fits in the same space no matter which one it is. So that's why they're kind of boxy like this.

So let's look at Macs here. So Macs for a long time now, all MacBooks just come with SSD's. That's the only option. There is no option to get a hard drive in there. There's not enough space in there. They're very thin and light. Even awhile ago, like back with the first MacBook Air, you could get a SSD in it. So you can see it's been around for awhile. But now it's just the only option just to have a SSD. Desktops like the iMac you can still configure with a hard drive but you can also configure them with a SSD and there's the hybrid option that Apple offers called the fusion drive which means you get both. You get a SSD and a hard drive and basically it's trying to use the SSD to read things that are read often and the hard drive for things that are stored and not read that often. So software is kind of handling it to give you basically 90% of the performance of a SSD but not as at high a cost because it's storing a lot of stuff on the hard drive.

If you look at, like say, configuring a MacBook Pro right now all the options are SSD no matter which model you choose they are all SSD options. But an iMac, for instance, you have on the lower end models the ability to have a regular hard drive and also the ability to have a fusion drive and go all the way up to a SSD. So depending upon what speed you need and how much money you've got in your wallet you can use any of these.

So that basically sums that up. One little bonus term here. If you are talking about a hard drive or a SSD you're talking about a disk with a k. The disc with a c, that's an actual optical piece of media like say a CD or DVD or you know like a blue ray. That's disc with a c. So if you want to use these terms correctly remember use k for a hard drive or SSD and c for an actual piece of optical media.