Flash drives
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Description
USB Flash drives can be considered a modern day floppy disk. What makes these little stick modern is that they can are removable and rewritable. Their storage capacity can range from a just a few gigabytes to over 200 gigabytes. The price of a flash drive depends on the number of GB's or gigabytes it can hold, the more GB's the more expensive its going to be. These small sticks have become so popular that most computers and laptops do not have a floppy disk drive any more but instead multiple USB ports. Flash drives are supported by most computers used today and their operation systems, like Windows, Mac OS X, Linux. Flash drives can store more data and transfer information faster then optical drives, and can be read by almost any system. The name drive was given because computers can read and write the data stored in the flash drive with the same system commands as a mechanical disk drive, the storage appears to the computer as just another drive. This durable little sticks can with stand almost anything that comes there with as long as nothing breaks that circuit board and/or connector. Most flash drives have a removable cap or lid or can retract into the body of the flash drive itself. Most drives use a standard type-A USB connector found on all modern day computers and lap tops, some drives have been made for other interfaces as well. Along with being small, fast and durable Flash drives do not require a battery either. Which makes using these little sticks convenient for anyone.
History
The first USB flash drives were sold by Trek Technology and IBM in 2000. The first name given was by the Singaporean company Treck Technology, they called it a "ThumbDrive", IBM then sold it has the "DiskOnKey." This "DiskOnKey" could hold more then five times a regular floppy disk, which at the time could only hold 1.44 megabytes, the USB drive help 8 MB. Today these flash drives have USB 2.0 connectivity. The fastest drives that are available use what are called dual channel controllers, but they aren't as fast as our modern day hard disk, or the high speed USB throughput. Just like their storage capacity, speed of a USB can be very different depending on the type of USB. Speeds can be given to consumers in Mbyte per second, Mbit per second, or optical drive multipliers. The normal fast drive can read up to 30 megabytes. Older USB drives that were considered "full speed" were limited to about 1 MB.
Technology
Due to recent advances in microprocessor technology, flash drive memories can combine old technology, low cost, low power consumption and small size. Before these advances these disks were very slow are reading and writing, they required complex high voltage drive circuitry, and could only be re-written after erasing the entire chip. Designers later broke up the erasure region into smaller fields, this meant that these fields could be erased individually without affecting any of the other fields. Flash drives can be seen as microprocessor systems that involve copying a field and pasting it into an off-chip buffer memory, fixing or modifying the data and then re-writing it into that same field that was erased. Computers recognize flash drives alot like they do hard disk drives, the controller system has full control where information is stored. With the exception Ipod and Zune most cheap MP3 players are nothing more than a battery operated flash drive, it is nothing more then a music playback decoder and a flash drive that can store files of any type.
References
USB flash drive- http://en.wikipedia.org/wiki/Flash_drives The History of USB Flash Drives- http://www.ehow.com/about_5152489_history-usb-flash-drives.html