A secure digital card (SD card) is a small flash memory device designed to provide high-capacity memory in a portable size. A standard SD card measures 32mm x 24mm x 2.1mm and weighs approximately 2 grams, whereas miniSD and microSD cards are physically much smaller but contain a similar capacity of memory. Variations of SD cards include Secure Digital High Capacity (SDHC), Secure Digital eXtended Capacity (SDXC), and Secure Digital Ultra Capacity (SDUC). These types of SD cards were designed to offer dramatically more capacity than a standard SD card.
To access data written on an SD card, users typically need a USB card reader. Once the card is inserted in the card reader and the card reader is connected to a computer, users can access and modify the files as they would with any other flash memory device. It’s important to note that SD cards are meant for temporary use; in fact, the data stored on an SD card has a maximum shelf life of 10 years.« Back to Glossary Index