Various Types of Memory cards

Often confused with: USB flash drives, plug-in RAM

Description: The Memory Stick was first released by Sony in 1998.

Memory Sticks use 10 conductors.

The physical dimensions are 21.5 mm wide by 50 mm deep by 2.8 mm thick.

Also known as: SD

Description: The specification for Secure Digital cards was jointly developed by Matsushita, SanDisk, and Toshiba starting in 1999, with the first cards being shipped in 2000.

Secure Digital cards use 9 conductors.

The physical dimensions are 24 mm wide by 32 mm deep by 2.1 mm thick.

Also known as: CF

Description: The CompactFlash card specification was originally developed by SanDisk in 1994.

CompactFlash cards use 50 conductors. The interface is electrically identical to the PCMCIA-ATA interface. The card appears to the host device as an IDE device, which is the same protocol used to communicate with hard drives.

The physical dimensions are 43 mm wide by 36 mm deep by either 3.3 mm thick for CompactFlash Type I or 5.5 mm thick for CompactFlash Type II. Most CompactFlash memory cards are type I.