A thumb drive is a portable USB (Universal Serial Bus) flash memory device for storing and transferring audio, video, and data files from a computer. As long as the desktop or laptop has a USB port and the flash drive is OS compatible, it should be easy to move data from the hard drive to the device – and to another computer – in a matter of minutes. The drive’s name comes from the fact that many have a retractable port connector, like a ballpoint pen, and are small enough to fit in a pocket. Other names include flash drive, jump drive, and thumb drive.
A flash drive usually has a large storage capacity and offers fast data transfers.
how to use it
Using a thumb drive is simple: the user inserts one end of the drive, which is equipped with a USB connector, into the USB port on a desktop or laptop and activates it. Once the drive is active, files can be dragged and dropped or copied and pasted into memory. The process is usually no more difficult than attaching files to an email or copying files to a disc, mp3 player or other storage device.
The thumb drive is considered an improvement over older floppy drive disks.
There are many different computer operating systems in use today, so most manufacturers configure their flash drives to work with a variety of systems. Before purchasing any portable storage device, the consumer should read the packaging carefully to make sure it will work with their computer system. Often, even users who have older operating systems can find compatible storage devices as long as those computers have a USB port.
How it works
Technicians classify flash drives as NOT AND, also called NAND, gate-style data storage devices. This technology works by storing data in blocks rather than randomly; as such, it does not function in the same way as a computer’s main memory systems – read-only memory (ROM) and random access memory (RAM). Using blocks instead of allowing random access allows the drive to store more information and be done at a lower cost.
Actual transfer speed depends on several factors, such as how fast the computer reads and writes to the device. Generally, the advertised speed of a flash drive is the read speed because it is faster than the speed at which data can be written to it. Manufacturers often list the speed in megabytes per second (MB/s). The age of the drive and how it is being used – such as writing and erasing small files – also affects transfer speed.
Equipped with a large amount of memory, the flash drive is often considered an improvement over both older floppy disks and more modern compact discs. They can transfer data much faster than these older technologies. Because they are solid state – there are no moving parts – flash drives generally last longer and the data stored on them is more secure. Depending on storage size, flash drives can be anywhere from 128 MB to 32 GB or more; in comparison, a standard CD-ROM contains about 700 MB of data.
Even a pen drive with a relatively low storage capacity tends to provide plenty of space for all different types of files. Any file that can be stored on a computer’s hard drive can usually be copied to a flash drive, as long as there is enough memory. There are also programs that can be run directly from the drive, without needing to be installed on the computer first.
Pen drives do have a few limitations, including how many times they can be used. Each drive has a limited number of program-erase cycles (P/E cycles), which is the act of putting files onto the drive and erasing them. Typically, the device can go through 100,000 P/E cycles before the integrity of the unit is compromised and files become corrupted.
Another limitation concerns the way manufacturers build the devices. The NAND gate-style allows a user to program or read the data one byte or word at a time, but erases data in blocks. When only small amounts are erased, the storage capacity is reduced.
The NAND gate-style device may also cause the loss of data because of the way that the information is accessed. Reading data in one cell may trigger changes in the cells that surround it. Generally, a user must read the cell thousands of times before this occurs, however and rewriting the surrounding cells periodically may prevent this problem.
The computer chip in the drive can also wear out, causing the device to operate more slowly. The NAND gate-style method of programming and erasing files that are smaller than a block can also slow things down. This can make the device mark some blocks as bad, even though they are not completely full; trying to read bad blocks and remapping them can reduce the speed with which the device functions.
The CD-ROM standard holds about 700 MB of data.