Here we detail the different types of flash memory
CompactFlash | Secure Digital | xD-Picture Cards
Multimedia Cards | Smart Media | Memory Stick | Microdrive
xD Picture Cards as with other types of media can be used in serveral devices, it was developed jointly by Fuji film and Olympus . It was designed to meet the demands for more storage especially for users of digital photography.

Unsurprisingly as the two companies jointly developed the technology both brands include this method of storage extensively throughout their range.
A Multimedia Card is a solid state disk card with a 7-pin connector. The cards contain no moving parts and are extremely rugged, providing much greater protection of data than conventional magnetic disk drives.

MultiMedia Cards are commonly used in portable devices such as digital cameras, digital music players, and test equipment.
MultiMedia Cards weigh just 2 grams and are about the size of a postage stamp - 3.2cm long, 2.4cm high, and .14cm thick (1.26" x .94" x .06").
SmartMedia Memory Cards were introduced in 1996 by Toshiba. They were originally called SSFDC, which stood for Solid State Floppy Disk card, as they resemble a miniature floppy disk. Smart Media cards usually incorporate a single Flash chip and do not incorporate a controller. They depend on the host controller (digital camera, etc) to manage all memory reads and writes.

SmartMedia memory is the lightest and thinnest Flash media with dimensions of 45mm x 37mm, 0.76mm.
Memory Stick media is manufactured by Sony, SanDisk and Lexar and is primarily used in digital cameras, mobile phones and PDA's.

Memory Stick Pro is a new version of Memory Stick which is designed for the latest digital cameras and has a high speed data transfer rate of 1.8mb per second.
The dimensions of Memory Stick and Memory Stick Pro are: 21.5mm x 50mm x 2.8mm. Memory Stick Duo is a smaller version for compact devices with dimensions of just 20mm x 31mm x 1.6mm.
Microdrive is not a flash memory card like the various other formats. Microdrive is a small portable hard disk and drawback of this is there are moving parts within the unit which means it is not as durable as the solid state options.

The benefits of it being a hard drive include larger capacity of storage and faster read/write access.
CompactFlash | Secure Digital | xD-Picture Cards
Multimedia Cards | Smart Media | Memory Stick | Microdrive
