Flash drives may present a significant security challenge for some organizations. Their small size and ease of use allows unsupervised visitors or employees to store and smuggle out confidential data with little chance of detection. Both corporate and public computers are vulnerable to attackers connecting a flash drive to a free USB port and using malicious software such as keyboard loggers or packet sniffers.
Particularly with the advent of USB, external hard disks have become widely available and inexpensive. External hard disk drives currently cost less per gigabyte than flash drives and are available in larger capacities. Some hard drives support alternative and faster interfaces than USB 2.0 (e.g., Thunderbolt, FireWire and eSATA). For consecutive sector writes and reads (for example, from an unfragmented file), most hard drives can provide a much higher sustained data rate than current NAND flash memory, though mechanical latencies seriously impact hard drive performance.
It's never been easier to take all the files, data or media you want with you wherever you go. Generally about the size of a stick of gum, a USB flash drive lets you store any file from your computer so you can save it, transport it, and load it onto another computer in seconds. You simply plug the flash drive into your USB port and drag any files you want onto its icon on your desktop. Best of all, flash drives have no internal moving parts, so they're very resistant to breaking by being bumped or dropped.