SD card

Updated: 02/04/2024 by Computer Hope

Short for Secure Digital card, the SD card is one of the more common types of memory cards used with electronics. The SD technology is used by over 400 brands of electronic equipment and over 8000 different models, including digital cameras and cell phones. It is considered the industry standard due to its wide use.

Types of SD cards

The three versions of the SD card, with their physical dimensions, are shown below.

  • SD - 32mm x 24mm x 2.1mm.
  • MiniSD - 21.5mm x 20mm x 1.4mm.
  • MicroSD - 15mm x 11mm x 1.0mm.

SD card examples

Storage types

In addition to the physical dimensions there are the following SD storage types that define the capacity of the card.

  • SDSC (secure digital standard capacity) - Up to 2 GB.
  • SDHC (secure digital high capacity) - From 2 GB to 32 GB.
  • SDXC (secure digital extended capacity) - From 32 GB to 2 TB.
  • SDUC (secure digital ultra capacity) - From 2 TB to 128 TB.

Speed classes

The speed classes of SD cards include Class 2, 4, 6, 10, UHS (ultra high speed) Speed Class 1 and 3, and Video Speed Class (V6, V10, V30, V60, V90).

How can I read an SD card on a computer?

A desktop and laptop computer can open and read any SD card with a card reader capable of reading the desired SD card size. If your computer does not have an SD card reader or one with the wrong slot size, an external USB (universal serial bus) card reader may be purchased.

What is the storage type of SD card?

SD cards use NAND flash memory. When formatted, the system format used is often FAT32 or exFAT.

Camera terms, Computer acronyms, Memory cards, Memory terms, MicroSD, MiniSD, Phone terms, Removable disk, SD, Storage device