Computer storage devices have changed a lot over the years, and it’s now possible to store more data than ever on a small one. Computers used hard disk drives for decades to store large amounts of data. But, looking back, the drives were ripe with flaws that led to failure and data loss. Today, computers use much more reliable flash memory.
Similarly, CDs were useful for storing a variety of content. But storage quickly became cheaper, and users stopped relying on CDs. But now, an even better solution exists where users can store all their data remotely so that it is accessible at all times and on any device. So, let’s take an in-depth look at some of the most common types of computer storage devices.
1. CD/ DVD

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CDs and DVDs may sound like an antiquated way to store data, but they were once the king of data storage. The downside is that a single disc really couldn’t hold that much data, especially as file sizes grew. However, discs made it possible to move data between computers before flash memory made USB flash drives practical.
But before CDs and DVDs became mainstream, large floppy disks made it possible to store and transfer data. To put capacities in perspective, the early 8″ floppies could hold about 100KB. Later, 3.5″ floppy disks made their way to personal computers and could hold about 1.5 to 2MB. In contrast, most CDs hold a whopping 650MB, and DVDs are 4.5GB.
Of course, there are also other types of discs, like Blu-ray, that hold even more content. However, the underlying concept remains the same. But what really changed the game for CD technology was the ability to write to them.
Early PC CD drives could only read data and couldn’t write to discs. Once CD burners became common, people started storing data like never before.
2. Hard Disk Drive
While CD and DVD storage really defined a generation, the hard disk drive still remains one of the most used types of memory. Mechanical hard drives come in two primary sizes for consumer use.
Large 2.5″ drives usually come in desktop computers, whereas laptops use a significantly smaller 2.5″ drive. While their sizes vary greatly, the technology essentially remains the same.
Metal platters store information, almost like a CD or DVD. The information is written and read with a special head on an arm that moves back and forth.
The platter spins very fast, which allows a large amount of information to be quickly added and removed. Over the years, hard drive technology has greatly improved, making it possible to stack multiple platters to fit even more information.
3. Solid State Drive
Solid-state drives are the next evolution in computer storage. In recent years many computer manufacturers have foregone spinning hard drives in favor of flash memory. Hard disk drives are great for storing large amounts of information because they are so cheap. However, there are several limitations and some major flaws.
- PCIE x 4 hard disk interface
- 4 TB size
- Great for gaming (up to 7300MB/s)
- Compatible with PS5 consoles
Because hard disk drives have moving parts, they are prone to failure. Of course, everything in a computer is prone to failure, but the addition of moving parts is a weak point.
Similarly, they are bound by the speed at which the head reads and the drive spins. Solid-state drives have neither of these weaknesses because there are no moving parts, and their speed is only limited by their modules and controllers.
In addition, solid-state drives are more energy efficient and produce no noise. Therefore many people are willing to use a smaller hard drive if it means a better experience. But an even newer take on the SSD is the M.2, which connects directly to a PCIe slot on the motherboard. These are small chips that use a much faster PCIe protocol instead of the traditional SATA connection.
4. Memory Card
Memory cards are another fading form of storage, but many devices surprisingly still use these little chips designed for cameras. If you aren’t very familiar, memory cards are small pieces of plastic that hold a flash memory chip. Like hard drives and other storage formats, memory card capacities have grown exponentially over the years while still retaining basic form factors.
- Shot speeds of up to 130MB/s
- 4K UHD video quality
- Transfer speeds of up to 180MB/s
Speaking of form, there are actually numerous different types of memory cards. The most common are SD and microSD cards. For over two decades, the SD card has been the standard for cameras. As cameras became increasingly more compact, they required a smaller memory card. Devices like GoPro cameras really drove demand for these tiny storage devices.
However, the number one use for memory cards today is mobile phones. Android phones like the Samsung Galaxy still supported expanding internal memory with an SD card until very recently. But new devices like the Nintendo Switch and Steam Deck also take advantage of SD cards. There are also plenty of other memory cards like CompactFlash and even Sony’s MemoryStick.
5. Flash Drive
Flash Drives are some of the most popular storage devices because they allow a user to easily connect and transfer files. As their name suggests, flash drives use flash memory, much like solid-state drives. This means they have no moving parts and provide rapid transfer speeds. While flash drives reliably hold data, their USB connection is a major point of failure.
- Transfers 4GB files in just 11 seconds
- Up to 400MB/s USB 3.13 read speeds
- Backward compatible with USB 3.0/2.0
- Enough space for 63,730 photos or a maximum of 12 hours of 4K video
- Up to 256GB of storage space
- 5-year limited warranty
Even so, flash drives are an extremely reliable way of both storing and transferring data. You can even transfer files between Windows and Mac computers.
Like other memory types such as SD cards, flash drives have gotten very large in capacity. But a growing problem is the adoption of USB-C ports on devices like Macs, which then require an adapter to use older USB-A flash drives.
6. RAM
RAM, or random-access memory, is completely different than all of the other types of memory we’ve covered so far. RAM differs from other technology, like flash memory, because it is not designed to store data. If you look at a stick of RAM, you’ll quickly notice there are several chips on it that resemble those used on flash memory.
With that in mind, RAM stores a small amount of data on these chips. The data comes from the hard drive and waits to go to the processor. Having large amounts of RAM means the computer can process more data by having it ready to go. RAM also comes in different types, such as DDR4 and DDR5, which dictates its speed and capabilities.
7. Cloud/ Server Storage
The final type of storage we will cover is cloud storage. This is where users store data on a remote device. Servers were common in most businesses because they allowed all of the company’s data on a single computer system.
All the computers connected to that network could then access the server’s files. But they were also used for other purposes like website hosting. As internet speeds got faster, many companies started paying for cloud storage rather than managing their own local servers.
The benefit is that users can access the data from anywhere, and this type of storage is often more reliable. But costs are also significantly cheaper, which has paved the way for personal cloud storage like iCloud and Microsoft OneDrive.