What Is a Thumb Drive?

A thumb drive is one of the many names associated with USB flash memory sticks. There are many related generic and brand-specific names, a reasonably comprehensive list of which can be found on the page covering all the terms that redirect to Wikipedia’s article. The term “Thumb Drive” came about because the dimensions of a standard USB memory stick are roughly similar to that of an average adult human thumb.

Use Cases and Competition

Thumb drives are a form of removable storage media. They superseded optical storage media such as the CD and DVDs as the removable storage media of choice. They were also the final nail in the coffin for floppy disks to be replaced by optical storage media.

Unlike floppy disks, thumb drives offered significantly more storage space and improved performance, all in a smaller form factor. Thumb drives also aren’t sensitive to magnetic fields or other electromagnetic interference and don’t have any moving parts making them more durable.

Compared to optical media, thumb drives offer greater storage capacity, faster read and write speeds, and smaller form factors. Optical media are vulnerable to scratches, whereas thumb drives are generally well protected in standard metal or plastic cases and can be further ruggedized.

Thumb drives are handy for transferring files from one device to another when physical access to both is possible. In the modern world, small files such as images or documents may be more quickly transferred over the Internet. Larger files, though, have to deal with relatively slow Internet speeds and require access to a cloud hosting service.

External hard drives are reasonable alternatives when dealing with substantial thumb drives. Options have much larger capacities and can support the latest high-speed USB standards. External hard drives can also be cheaper than large thumb drives. Thumb drives still win on portability, though external m.2 SSDs can come pretty close.

Timeline

Flash memory was invented in the early 1980s. The first thumb drives were sold in the year 2000. Early thumb drives used the USB 1.1 interface, limiting performance to around 1.5MB/s when allowing overhead transmission. By 2002 thumb drives were available using USB 2.0, offering speeds of around 35MB/s when accounting for overheads. As newer generations of the USB protocol have been standardized, thumb drives have typically followed. USB 3 thumb drives are now using the USB-A and USB-C connectors every day.

A standard thumb drive may have 8, 16, or 32GB storage. Much larger models, however, are available, with up to 2TB of storage. Exceptionally high-capacity models of thumb drives tend to have a price premium, as you might expect. This can make external hard drives of comparable capacity cheaper. External M.2 SSDs may not necessarily be able to compete on price, being fairly high-end themselves. However, they can offer even more storage space and are more likely to support higher transfer speeds.

Risks to Consider

When using a known thumb drive, you must account for two risks. The first is that the thumb drive is pretty small, making it easy to misplace. Many thumb drives feature an attachment point for a keychain that can help keep track of them. The second risk is connecting a known thumb drive to an untrusted device. Some malware is known to opportunistically infect thumb drives and use them to spread to other computers.

When dealing with an unknown thumb drive, there are even more risks. Without plugging it into a computer, there is no way to know the drive’s contents. Unfortunately, malware can launch itself, infecting your computer automatically. This can happen even if you immediately scan the thumb drive with an antivirus tool after connecting the drive.

While not directly relevant to the average person, it is believed that the Stuxnet virus was introduced to an Iranian nuclear facility because a curious employee plugged in an infected thumb drive that had been deliberately dropped in the car park.

Unfortunately, malware isn’t the worst possible outcome regarding unknown thumb drives. USB Killer is a hardware platform designed to look like a thumb drive; it doesn’t feature any storage. Instead, it features capacitors. These capacitors charge up from the 5V pin when connected to a USB port; after a short charging period, they discharge roughly 200V into the USB data lines.

This can – and is intended to – fry the circuitry. In many cases, this not only breaks the USB port but also fries the motherboard chipset breaking the computer. While replacing the motherboard in a desktop computer may be possible, this generally necessitates replacing the entire computer.

Conclusion

A thumb drive is one of many terms for a USB flash drive or USB memory stick and is a form of removable storage. The name came from the fact that they’re typically roughly the size of a thumb. Some novelty models may even look like a severed thumb.

Storage capacities vary from a few gigabytes to two terabytes. Many thumb drives operate at USB 3.0 speeds but can still be limited to USB 2.0 performance. Care should be taken when interacting with untrusted devices, as thumb drives can be infected with malware.