Universal Disk Format (UDF) version 1.50 and above has facilities to support rewritable discs like sparing tables and virtual allocation tables, spreading usage over the entire surface of a disc and maximising life, but many older operating systems do not support this format. Packet-writing utilities such as DirectCD and InCD are available but produce discs that are not universally readable (although based on the UDF standard). The Mount Rainier standard addresses this shortcoming in CD-RW media by running the older file systems on top of it and performing defect management for those standards, but it requires support from both the CD/DVD burner and the operating system. Many drives made today do not support Mount Rainier, and many older operating systems such as Windows XP and below, and Linux kernels older than 2.6.2, do not support it (later versions do). Essentially CDs/DVDs are a good way to record a great deal of information cheaply and have the advantage of being readable by most standalone players, but they are poor at making ongoing small changes to a large collection of information. Flash drives' ability to do this is their major advantage over optical media.
Audio tape cassettes and high-capacity floppy disks (e.g., Imation SuperDisk), and other forms of drives with removable magnetic media, such as the Iomega Zip and Jaz drives, are now largely obsolete and rarely used. There are products in today's market that will emulate these legacy drives for both tape and disk (SCSI1/SCSI2, SASI, Magneto optic, Ricoh ZIP, Jaz, IBM3590/ Fujitsu 3490E and Bernoulli for example) in state-of-the-art Compact Flash storage devices – CF2SCSI.
Capacity - More so than any other feature, capacity will drive the price of a flash drive up the most. So before you make a purchase, consider how much you’re willing to spend on a flash drive and weigh that against how much capacity you’ll likely need. A flash drive with 16GB can cost you as little as $10, while a 128GB one will run up to $60 or more.
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.
As highly portable media, USB flash drives are easily lost or stolen. All USB flash drives can have their contents encrypted using third-party disk encryption software, which can often be run directly from the USB drive without installation (for example, FreeOTFE), although some, such as BitLocker, require the user to have administrative rights on every computer it is run on.
Audio tape cassettes and high-capacity floppy disks (e.g., Imation SuperDisk), and other forms of drives with removable magnetic media, such as the Iomega Zip and Jaz drives, are now largely obsolete and rarely used. There are products in today's market that will emulate these legacy drives for both tape and disk (SCSI1/SCSI2, SASI, Magneto optic, Ricoh ZIP, Jaz, IBM3590/ Fujitsu 3490E and Bernoulli for example) in state-of-the-art Compact Flash storage devices – CF2SCSI.
Third generation USB flash drives were announced in late 2008 and became available in 2010.[citation needed] Like USB 2.0 before it, USB 3.0 dramatically improved data transfer rates compared to its predecessor. The USB 3.0 interface specified transfer rates up to 5 Gbit/s (625 MB/s), compared to USB 2.0's 480 Mbit/s (60 MB/s).[citation needed] By 2010 the maximum available storage capacity for the devices had reached upwards of 128 GB.[7] USB 3.0 was slow to appear in laptops. As of 2010, the majority of laptop models still contained the 2.0.[23]
Features: 100% New&High Quality Storage Capacity: 32GB Support USB version 2.0 and 1.0 Easy plug and play installation Interface: USB 2.0; Due to the inner system and procedure data will occupy some space and the real capacity will reduce lightly Stylish lightweight; portable,new concept modeling,classic fashion,compact Brisk High Speed; plug and play, in line with USB 2.0 specification, data transfer speed. Compatible with Windows 7/Windows 8, Windows 10, Windows XP, Windows Vista, Mac OS 9.0,Hi-Speed USB 2.0 port required for high speed transfer Support solution for Linux kernel version 2.4 or later version Driveless for OS 9X or up Durable solid-state storage No external power is required 4.5V ~ 5.5V from USB port The data read speed: 8M-18M/S(USB2.0) The data write speed: 3M-7M/S(USB2.
Most flash drives ship preformatted with the FAT32, or exFAT file systems. The ubiquity of the FAT32 file system allows the drive to be accessed on virtually any host device with USB support. Also, standard FAT maintenance utilities (e.g., ScanDisk) can be used to repair or retrieve corrupted data. However, because a flash drive appears as a USB-connected hard drive to the host system, the drive can be reformatted to any file system supported by the host operating system.

Specially manufactured flash drives are available that have a tough rubber or metal casing designed to be waterproof and virtually "unbreakable". These flash drives retain their memory after being submerged in water, and even through a machine wash. Leaving such a flash drive out to dry completely before allowing current to run through it has been known to result in a working drive with no future problems. Channel Five's Gadget Show cooked one of these flash drives with propane, froze it with dry ice, submerged it in various acidic liquids, ran over it with a jeep and fired it against a wall with a mortar. A company specializing in recovering lost data from computer drives managed to recover all the data on the drive.[64] All data on the other removable storage devices tested, using optical or magnetic technologies, were destroyed.
With wide deployment(s) of flash drives being used in various environments (secured or otherwise), the issue of data and information security remains important. The use of biometrics and encryption is becoming the norm with the need for increased security for data; on-the-fly encryption systems are particularly useful in this regard, as they can transparently encrypt large amounts of data. In some cases a secure USB drive may use a hardware-based encryption mechanism that uses a hardware module instead of software for strongly encrypting data. IEEE 1667 is an attempt to create a generic authentication platform for USB drives. It is supported in Windows 7 and Windows Vista (Service Pack 2 with a hotfix).[47]
Floppy disk drives are rarely fitted to modern computers and are obsolete for normal purposes, although internal and external drives can be fitted if required. Floppy disks may be the method of choice for transferring data to and from very old computers without USB or booting from floppy disks, and so they are sometimes used to change the firmware on, for example, BIOS chips. Devices with removable storage like older Yamaha music keyboards are also dependent on floppy disks, which require computers to process them. Newer devices are built with USB flash drive support.
Some manufacturers deploy physical authentication tokens in the form of a flash drive. These are used to control access to a sensitive system by containing encryption keys or, more commonly, communicating with security software on the target machine. The system is designed so the target machine will not operate except when the flash drive device is plugged into it. Some of these "PC lock" devices also function as normal flash drives when plugged into other machines.
With their paper-slim profiles, Ultrabooks and tablets are barely thick enough for a USB port. That's why some of the bulkier drives on this list are not ideal for those devices. Meanwhile, Samsung’s Fit drives are slim and compact, about the size of your thumb nail. This unobtrusive storage is constructed with a metal casing that is resistant to the elements and NAND flash technology. With USB 3.0 tech you can expect fast read speeds, while the price is easy to stomach. Just make sure to attach it to a lanyard, so you don't lose it.
A drawback to the small size of flash drives is that they are easily misplaced or otherwise lost. This is a particular problem if they contain sensitive data (see data security). As a consequence, some manufacturers have added encryption hardware to their drives, although software encryption systems which can be used in conjunction with any mass storage medium will achieve the same result. Most drives can be attached to keychains or lanyards. The USB plug is usually retractable or fitted with a removable protective cap.
With wide deployment(s) of flash drives being used in various environments (secured or otherwise), the issue of data and information security remains important. The use of biometrics and encryption is becoming the norm with the need for increased security for data; on-the-fly encryption systems are particularly useful in this regard, as they can transparently encrypt large amounts of data. In some cases a secure USB drive may use a hardware-based encryption mechanism that uses a hardware module instead of software for strongly encrypting data. IEEE 1667 is an attempt to create a generic authentication platform for USB drives. It is supported in Windows 7 and Windows Vista (Service Pack 2 with a hotfix).[47]
“The Samsung BAR is incredibly small and easily portable, measuring just under 2-inches long,” our tester said. He added, “It's also extremely durable: waterproof, shockproof, as well as x-rays and magnets [proof].” The included key ring adds to its portability, according to our reviewer. On the flip side, he called the transfer speeds “decent but mostly unremarkable.” Our tester concluded, “Most of the BAR's problems are due to Samsung releasing a newer, cheaper model, the BAR Plus.”

Also, HP has introduced a USB floppy drive key, which is an ordinary USB flash drive with additional possilibility for performing floppy drive emulation, allowing its usage for updating system firmware where direct usage of USB flash drives is not supported. Desired mode of operation (either regular USB mass storage device or of floppy drive emulation) is made selectable by a sliding switch on the device's housing.[51][52]
Some manufacturers, aiming at a "best of both worlds" solution, have produced card readers that approach the size and form of USB flash drives (e.g., Kingston MobileLite,[65] SanDisk MobileMate[66]) These readers are limited to a specific subset of memory card formats (such as SD, microSD, or Memory Stick), and often completely enclose the card, offering durability and portability approaching, if not quite equal to, that of a flash drive. Although the combined cost of a mini-reader and a memory card is usually slightly higher than a USB flash drive of comparable capacity, the reader + card solution offers additional flexibility of use, and virtually "unlimited" capacity. The ubiquity of SD cards is such that, circa 2011, due to economies of scale, their price is now less than an equivalent-capacity USB flash drive, even with the added cost of a USB SD card reader.

External flash drives use what's known as "solid-state" storage, which can store, back up, and retrieve data using only electronic circuits. Solid-state drives do not contain any moving mechanical parts, which enables them to access data quickly and easy. A typical flash drive allows up to 100,000 write/erase cycles before the integrity of the data starts to degrade. This translates to around a 10-year lifespan, depending on how much it is used.
×