Flash Drives vs. Thumb Drives

Sometimes called flash memory, flash storage is non-moving, non-volatile memory. Unlike with hard drives, flash drives do not have any moving parts. Instead, flash uses NAND memory, which doesn’t require power to preserve data and uses electric circuits to write the data onto metal-oxide semi-conductors or microchips. Flash memory is also not easily corrupted. Flash memory is often used in conjunction with other types of memory like SSD storage. Different kinds of storage drives that are external to a device will use flash memory. Some might connect via a USB-A or a USB-C cable, while others—like thumb drives—have the USB plug embedded into the drive’s outer casing. A few examples of flash memory form factors that are NOT presented in a thumb drive format are SD Cards, credit card drives, and external portable SSD drives. We’ll explain the benefits of those more in detail later in this article.

Click here to learn more about the difference between Flash and SSD Memory

A thumb drive is a type of external flash drive that connects directly to a device using its USB-A or USB-C port. Thumb drives are one of the most economical ways to facilitate data transfer. The USB interface is embedded directly into the drive’s exterior housing. A thumb drive does not need a cable. Sometimes the USB interface might be encased inside the thumb drive’s housing. In that case, the user can expose or hide the interface by sliding a button forward or backward with their thumb. This protects the drive and prevents debris from entering the interface. Thumb drives are usually flat (about 2 cm high) and no longer or wider than a thumb. USB drives derive power from their connection to devices.

The main difference between thumb drives and other external flash drives are that other flash drives require a USB cable or a card reader to connect to devices, while a thumb drive’s plug is embedded in its housing. Also, other flash drives often have the capacity to store far more data (often up to 4TB while flash drives typically stop at 8GB) and have much faster read and write speeds (beyond 10GBPS for USB 3.0 ports) due to their incorporation of Solid State drives (SSDs).  Most modern SSDs are comprised of multiple sections of flash storage that work together to operate as quickly as possible. On the other hand, most external flash drives are not as compact as thumb drives because they usually also contain SSD (which requires more space) along with flash memory. 

Caution should always be used when using thumb drives as they can be easily broken, misplaced or pose a significant security risk for you or your organization. Never plug a thumb drive into your device if you are not aware of its origin or if your thumb drive has been lost or misplaced and found again. Thumb drives are often a source of infection from computer viruses, malware and spyware. Also, if stolen, the sensitive or proprietary data on your thumb drive could easily compromise your organization’s reputation and financial security since most thumb drives are not password protected or encrypted.

The exterior design of a flash memory device can take on a number of visible characteristics but still support storage capacities similar to less portable storage (like true hard drives). Thumb drives are described above and are quite ubiquitous now due to their low cost. The USB interface and connection used will dictate the read/write speed, which is measured as megabytes per second (MBps). Both USB Type-A and USB Type-C interfaces use the same units of speed to transfer data. Data transfer with USB 3.1 (600MBps) is slower than USB 3.1 Gen 2 (1,250MBps), or USB 3.2 Gen 2 (2.4GBps) which was launched in 2017. Thunderbolt ports look exactly like USB-C ports, but they do everything faster; up to 40GBps compared to 20GBps on USB-C ports.

The USB-C protocol became standard in 2014. As a result, the thumb drive’s connector or plug has taken on a different appearance in the years following. Before that the rectangular USB-A ports were in most devices. Now, users can expect to see more USB-C thumb/pen drives that are smaller, oval-shaped and reversible (meaning there is no right-side up way to plug in the cable or connection) as well as credit card USB drives. USB-C drives are also backward compatible and some cables have one of each plug on either end. While USB-A drives will not disappear immediately, consider eventually upgrading your flash memory device. USB-C ports and drives have faster data transfer speeds, can transmit 4K video, and has significantly faster charging of devices.

Lightning Drives and cables work exclusively with most Apple products (except for 3^rd generation iPad Pros and later) but are also called thumb drives. Apple iPhones and iPads often carry a Lightning interface. Although Lightning and USB-C both provide connection, communication and power, they are not the same. USB-C has faster transfer speeds compared to lightning (40GBps vs 480MBps).

Credit Card/Business Card USBs are the dimensions of a debit or credit card but slightly thicker. They use a USB-C interface, which is folded or slid into a cutout within the card. Unlike USB-C thumb drives, the flash card drives are usually not reversible since one side of the card has a design or brand logo on it. These cards have been popular swag gifts to customers from financial institutions.

SD and microSD cards also use flash memory. These flat and thin rectangular cards (between 1 and 3mm thick) are likely the smallest and possibly the lightest form factor for flash memory. But they often carry more memory than thumb drives. Besides storage in the cloud, MicroSD cards are often the main source of memory used within mobile phones and digital cameras. MicroSD card slots on phones are an additional form of local storage now that mobile data is directed to the cloud and phones have more internal storage. Keep in mind that external SD and microSD cards require a card reader if the device does not have a slot for the card. Also, due to their small stature, they can be easily misplaced or broken.

External Portable or Bulk SSD flash drives like Western Digital’s popular My Passport have the capacity to store more memory than any of the other form factor, and they can cost considerably more as well. These drives are often marketed for their durability and long lifespan (often supporting up to 100,000 write cycles). Although they are frequently mistaken for traditional external hard drives, compared to SSD flash drives, the former must be handled like fine China. Many SSD drives are so much tougher and are even waterproof and drop proof. As a result, SSD drives can take on a number of physical characteristics. SSD flash drives are distinct from thumb drives in that they are much larger in size, integrate both flash and SSD memory and in addition to costing more money, they require cables to connect to devices.

A drive’s file system or formatting dictates how data is organized and stored by the flash memory on the drive. All drives must be formatted before they can be used. Some drives can be purchased with formatting already in place. Nand Flash memory can be formatted in several ways, including NTFS/NTFS5, HFS+, ZFS, FAT32, APFS, and exFAT. FAT32 is the default filing system for most flash drives. But not all drives are automatically formatted with FAT32. In some cases, it may be advantageous to reformat a file system to increase compatibility and speed with the device that will read or write data to it. The file system will also help determine the cards read/write cycle and by default its lifespan.

Sometimes a memory drive is divided into several partitions. There are many reasons for adding partitions to a flash drive. One of the main advantages to adding one or more partitions is to create the ability to read and write data from more than one operating system on the same drive. Other reasons might include enabling encryption within one partition but not others, reducing the spread of possible corrupted or damaged data, and preventing the co-mingling of system data and user data to maximize space. However, on the downside, partitioning drives can also reduce available space for larger files.