(Secure Digital Memory Card) A flash memory card that provides storage for digital cameras, cellphones and PDAs. SD Memory Cards use the same 32x24mm form factor as the MultiMediaCard (MMC), but are slightly thicker (2.1mm vs. 1.4mm), and SD Card readers accept both formats. Introduced in 1999 by Panasonic, Toshiba and SanDisk, cards up to 2GB are available.
Learn also: Raspberry Pi Backup SD Card.
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