Popular Products > Computers > Secure Digital

Secure Digital, popularly known as SD, is a flash memory card format that is a product of a collaboration between Matsushita, SanDisk and Toshiba. These three companies came together to develop and promote a secure memory card which they called the SD Memory Card.

Besides promoting SD memory cards, Matsushita, SanDisk and Toshiba have also formed the industry-wide SD Association (SDA). A growing number of technology and content companies are part of the SDA, which aims to set industry standards and promote wide acceptance of the SD memory card.

Secure Digital cards are based on the format of Multimedia cards, but have certain advantages. Primarily, the asymmetrical shape of Secure Digital cards ensures that they are not inserted upside down. Multimedia Cards were thinner than Secure Digital cards and could break easily. In addition, recessions are made to the surface of the Secure Digital Cards during manufacturing which prevent damage to the contact areas of the cards. Secure Digital was initially available in limited capacities of 32MB and 64MB. However, they are now sold in 4GB storage capacity, with up to 32GB storage capacity for SDHC cards.

The SD Memory Cards can be easily accessed if you use CompactFlash or PC card slots that come with an adapter. The MiniSD or MicroSD cards are inserted directly into SD slots using a physical interface adapter. You can also use card readers that access Secure Digital cards using interface ports such as Firewire, USB or the parallel printer port. Data on a Secure Digital card can also be read through a floppy disk drive with a FlashPath adapter.

Different types of Secure Digital cards are now available. The SD Plus card features an integrated USB connector that allows the card to be directly plugged into a USB port without requiring a card reader. The latest SD cards are available with a digital display that shows the about of free storage space and also have Wi-Fi capability.

Secure Digital cards are used in many different devices. Digital cameras use this memory card format for storing pictures. Many brands such as Casio, Canon, Kodak and Panasonic also use this memory card format in their products. Handheld computers and PDAs use Secure Digital cards for storing images, media files and sound clips. Global Positioning Systems or GPS receivers use Secure Digital cards for storing maps and route data.