The SD card has been around since 1999, but has really only taken off in the last year. It’s a secure digital memory card, though originally the SD stood for something else altogether, that is, Super Density. The secure aspect was an encryption process added to the already existing Multi-media card, in an attempt to overcome piracy problems.
There is now an SDA – an association – and they have issued detailed specifications for the non-security aspects of the SD memory card standard. The cards have quickly gone from having megabytes of memory to gigabytes. The current versions are highly secure, and very small. Some only stamp-sized. They have no moving parts and retain data even power is turned off.
SD cards can be used in a variety of SD enabled digital products, from music players to cellular phones, from handheld PCs to digital cameras, from digital video recorders to smart phones, car navigation systems and electronic books.