- What's Flash Memory?
- NOR/NAND Flash Memory
- Memory cards: Form defines function
- What is CompactFlash?
- What is Microdrive?
- What is Memory Stick?
- What is SD/MMC/RS-MMC/MMC Micro/miniSD/MicroSD?
- What is Smart Media?
- What is XD-Picture card?
- Flash Drives with everything
- What are USB keys?
- What are ExpressCards?
USB keys -- sometimes referred to as Thumb drives, Pen Drives or Flash Drives or other such appellations -- are in essence NAND Flash Memory chips attached to some simple logic circuitry for read/write operations and a USB plug.
Sizes for USB keys run from 8MB up to 8GB with accordingly larger price tags as you require more storage. They're primarily designed as storage media for PC applications, although there are devices that will enable you to use USB keys with other hardware such as home game consoles. Older USB Keys work from the slower USB 1.1 specification, while current devices use the quicker USB 2.0 specification.
USB keys come in a wide variety of shapes and sizes, including 'novelty' types that can resemble everything from bananas to swiss army knives. The main things to look for are durability (particularly handy if you want to attach the device to your key chain) and memory capacity. Naturally, if you plan to store video files and other memory-hungry data, you'll want a device with at least 2GB of storage space.What are ExpressCards?
ExpressCard is a new hardware standard for PCs and notebooks. It supports both PCI Express and USB 2.0, and compatible devices are often used for memory purposes. Video cameras are beginning to emerge that use ExpressCards high-speed media for recording data -- this can then be removed and inserted straight into your computer for editing and/or storage.
ExpressCard supports two form factors, ExpressCard/34 (34mm wide) and ExpressCard/54 (54mm wide, in an L-shape), both of which will typically fit into the same ExpressCard slot. At present, still cameras do not use this format due to its hefty size, though it still represents a handy way of storing your photos and related media.