by David Hakala
A memory card is essentially portable RAM, electronic memory that you can put in your pocket and plug into various devices to use as storage. A USB flash drive is a type of memory card. So are the wafer-thin cards you slide into digital cameras, game consoles, etc. There are different types of memory cards made for different purposes.
CompactFlash memory cards can hold up to 12 GB of data each. They’re ideal for high-quality digital photography using single-lens reflex (SLR) cameras whose images exceed 10 MB each. There are two sizes of CompactFlash cards on the market. Type II is thicker than Type I. You can use a Type I CompactFlash card in a Type II slot but not vice versa. Make sure your device will fit the memory cards you buy.
The Memory Stick is a proprietary memory card format developed by Sony Corp. It’s found on Sony consumer devices and Sony-Ericsson cell phones. Memory Sticks come in three sizes. The original Memory Stick holds only 128 MB of data. The Memory Stick Select holds up to 256 MB. The Memory Stick Pro holds up to 8 GB. If you have a Pro-compliant device it will use the other two types of Memory Sticks, but an older device may not be able to use Pro Memory Sticks. Adding to the confusion, there are Memory Stick Duo cards, physically smaller units for small devices such as Playstation Portable. They hold up to 2 GB of data. Tiniest of all is the Memory Stick Micro designed for Sony-Ericsson phones; it also holds up to 2 GB.
The MultiMediaCard (MMC) is a format generally found in cameras and PDAs. It can also be used in devices that support SD Cards, but its maximum 1 GB capacity is less popular.
The Secure Digital or SD Card is the most popular format on the market. Its high capacity, relatively fast data transfer speed, ruggedness, and write-protect lock make the SD Card format popular in everything from cameras to MP3 players.
Less common or obsolete memory card formats you may run into on older devices include SmartMedia and xD-Picture Cards. They are of smaller capacity than the dominant memory cards of today.
David Hakala has perpetrated technology tutorials since 1988 in addition to committing tech journalism, documentation, Web sites, marketing collateral, and profitable prose in general. His complete rap sheet can be seen at http://www.linkedin.com/in/dhakala