Being part of support team of a tech store, one of the FAQs is the variety of Flash Memory available. Most digital cameras, music players, and PDAs use flash memory cards to store data. These small media cards hold anywhere from 8MB to 1GB of data. With assortment of cards available you should choose carefully.

People would ask 'what size flash card should I buy'. Answer to this depends is on what files/media you'll throw to the card. Office files onto your handhelds, 32MB would be sufficient. A 64MB should contain 13 MP3 songs, for the rocker in us, this is not enough. Same holds true for a pro photographer or a photo enthusiast, 256MB and above is suggested to store all those megapixel-Diana-Zubiri-wallpapers.

If you care to know, transfer rate of flash memory is about 1 MBps. New technologies and interfaces can double or triple that rate, but you will pay extra, nothing is free as we all know. I am taking it back, some things are free. Card memory is more expensive than hard drive pound-4-pound, bit-4-bit I should say. But the emergence of digital this and digital that makes us forget its price. We need small and removable memory. If you care to know part 2, the birth of these cards happened when megapixel digicams emerged in the mid-90s. A quick overview for you, SmartMedia (SM) is the first standards-based memory card to show up. Its large footprint is its drawback, about 2.7 square inches, compared with Secure Digital's (SD), 1.2 square inches. Its flexibility makes it vulnerable to damage. Also, some devices won't work with cards larger than about 16MB or 32MB. Do not expect to see few new devices using this type.

MultiMediaCard (MMC) is another pioneer. With its rigid plastic shell, it is less damage-prone. Same footprint and pin-out as its successor, the Secure Digital (SD) card. MMCs fit in SD devices but not vice-versa (SD cards are thicker). SD music players typically won't play audio from an MMC, because SD players require encrypted music. Most companies are currently phasing out MMC devices.

CompactFlash (CF) is old but far-from-dead flash memory champion. The living-legend of memory cards, we can say. More devices currently use CF than any other media type.
GB CF cards are available so users don't mind the size of CF cards. CF size: 1.4 by 1.7 by 0.2 inches. Sony created and supports the Memory Stick format across its product line, and several other manufacturers offer Memory Stick products as well. Memory Stick has an array on its own.

Secure Digital (SD) has the broadest support and brightest future. I love SD! It is small and can contain GB data. The drawback is that SD players, like Memory Stick players, require you to check out music from your PC. Knowing these things will save the buyer time, makes his money well-spent and will definitely make a job like mine, easier.

Source: ecBuyph.com Tech Support - April 2004