Hardware Reference
In-Depth Information
For additional protection of your data, some USB flash drives have a mechanical write-
protectswitch.Othersincludeorsupportpassword-protecteddataencryptionasanoption,
and most are capable of being a bootable device (if supported in the BIOS). Some
drives feature
biometric security
—your fingerprint is the key to using the contents of the
drive—whereas others include more traditional security software.
Some companies have produced bare USB flash drives that act as readers for MMC, SD,
xD-Picture Card, and Memory Stick flash memory cards. These USB flash readers are es-
sentially USB flash drives without flash memory storage onboard. You can use them as a
card reader or as a USB drive with removable storage.
Comparing Flash Memory Devices
As with any storage issue, you must compare each product's features to your needs. You
should check the following issues before purchasing flash memory-based devices:
• Which flash memory products does your camera or other device support? Although
adaptersallowsomeinterchangeofthevarioustypesofflashmemorydevices,forbest
results, you should stick with the flash memory type your device was designed to use.
• Which capacities does your device support? Flash memory devices are available
in ever-increasing capacities, but not every device can handle the higher-capacity
devices. Check the device and flash memory card's websites for compatibility inform-
ation.
• Are some flash memory devices better than others? Some manufacturers have added
improvements to the basic requirements for the flash memory device, such as faster
write speeds and embedded security. Note that these features usually are designed for
use with particular digital cameras only. Don't spend the additional money on en-
hanced features if your camera or other device can't use those features.
Only the ATA Flash cards can be attached directly to a laptop computer's PC Card slot.
All other devices need their own socket or some type of adapter to transfer data.
Figure
10.2
shows how the most common types of flash memory cards compare in size to each
other and to a penny.
Figure 10.2
SmartMedia, CompactFlash, MultiMediaCard, Secure Digital, xD-Picture Card, and Sony
Memory Stick flash memory devices. Shown in relative scale to a U.S. penny (lower right).
