The development of high-speed serial data interfaces such as USB made semiconductor memory systems with serially accessed storage viable, and the simultaneous development of small, high-speed, low-power microprocessor systems allowed this to be incorporated into extremely compact systems. Serial access requires far fewer electrical connections for the memory chips than does parallel access, which has simplified the manufacture of multi-gigabyte drives.
Flash memory combines a number of older technologies, with lower cost, lower power consumption and small size made possible by advances in microprocessor technology. The memory storage was based on earlier EPROM and EEPROM technologies. These had limited capacity, were slow for both reading and writing, required complex high-voltage drive circuitry, and could be re-written only after erasing the entire contents of the chip.
Motherboard firmware (including BIOS and UEFI) can be updated using USB flash drives. Usually, new firmware image is downloaded and placed onto a FAT16- or FAT32-formatted USB flash drive connected to a system which is to be updated, and path to the new firmware image is selected within the update component of system's firmware.[49] Some motherboard manufacturers are also allowing such updates to be performed without the need for entering system's firmware update component, making it possible to easily recover systems with corrupted firmware.[50]
Counterfeit USB flash drives are sometimes sold with claims of having higher capacities than they actually have. These are typically low capacity USB drives which are modified so that they emulate larger capacity drives (for example, a 2 GB drive being marketed as a 64 GB drive). When plugged into a computer, they report themselves as being the larger capacity they were sold as, but when data is written to them, either the write fails, the drive freezes up, or it overwrites existing data. Software tools exist to check and detect fake USB drives,[43][44] and in some cases it is possible to repair these devices to remove the false capacity information and use its real storage limit.[45]
"Nice device for bulky files....I have 2 of these flash drives and it's more convenient for me to store backups of my most important files on 2 of these flash drives than an external drive because it's easier for me to transfer my data files between 3 devices, carry the drive around in my pocket, and the transfers are easy and fast since it's USB 3.0"
As of 2011, newer flash memory designs have much higher estimated lifetimes. Several manufacturers are now offering warranties of 5 years or more. Such warranties should make the device more attractive for more applications. By reducing the probability of the device's premature failure, flash memory devices can now be considered for use where a magnetic disk would normally have been required. Flash drives have also experienced an exponential growth in their storage capacity over time (following the Moore's Law growth curve). As of 2013, single-packaged devices with capacities of 1 TB are readily available,[54] and devices with 16 GB capacity are very economical. Storage capacities in this range have traditionally been considered to offer adequate space, because they allow enough space for both the operating system software and some free space for the user's data.
The applications of current data tape cartridges hardly overlap those of flash drives: on tape, cost per gigabyte is very low for large volumes, but the individual drives and media are expensive. Media have a very high capacity and very fast transfer speeds, but store data sequentially and are very slow for random access of data. While disk-based backup is now the primary medium of choice for most companies, tape backup is still popular for taking data off-site for worst-case scenarios and for very large volumes (more than a few hundreds of TB). See LTO tapes.
Flash memory cards, e.g., Secure Digital cards, are available in various formats and capacities, and are used by many consumer devices. However, while virtually all PCs have USB ports, allowing the use of USB flash drives, memory card readers are not commonly supplied as standard equipment (particularly with desktop computers). Although inexpensive card readers are available that read many common formats, this results in two pieces of portable equipment (card plus reader) rather than one.
On the more practical side our flash drives, also called thumbdrives or memory sticks are available in memory capacities from 64MB to 256GB. With memory capacities like that, we certainly have the options to cover whatever your data storage requirements may be. For more information on data storage capacities, check out our USB Flash Drive Capacity Guide.
Some file systems are designed to distribute usage over an entire memory device without concentrating usage on any part (e.g., for a directory) to prolong the life of simple flash memory devices. Some USB flash drives have this 'wear leveling' feature built into the software controller to prolong device life, while others do not, so it is not necessarily helpful to install one of these file systems.[39]
There's a lot to choose from when it comes to buying a flash drive. The most important thing to consider is size. The whole point of a USB drive is to store lots of data in a small space, so think about what kinds of files you'll want to house on your flash drive. Movies and music take quite a bit of space, so if you're carrying your whole entertainment library with you, you'll want a big thumb drive – at least 16GB. Books and other text-based documents require relatively little storage space, so people like students and working professionals using Microsoft Office would be happy transferring Word documents or Excel files with as little as 1GB of space. On the other hand, if you are using photo or music editing software, you'll want a USB flash drive with lots of storage capacity to transfer graphic and music files.
