Memory Stick cards are flash-type IC media used primarily in portable devices. It was designed by Sony to offer faster data transfer rates, as well as improved data security using MagicGate technology. It uses traditional flash memory. There are over 600 companies who support Memory Stick technology.
There are a few types of Memory Stick product. Memory Stick, Memory Stick Pro, Memory Stick Duo, and Memory Stick Pro Duo. All devices designed for Memory Stick technology are required to support all types of Memory Stick media.
Memory Stick Pro cards offer more memory and faster data transfers, and cost more than non-Pro products.
Memory Stick Duo cards are roughly half the physical size of a Memory Stick. To maintain compatibility between Duo and normal cards, an adaptor is available, which the Duo card slides into. Memory Stick and Memory Stick PRO are the same physical size. Memory Stick Duo and Memory Stick PRO Duo are also the same physical size.
The PSP uses Memory Stick Duo technology, and started offering support for Pro Duo cards with a recent firmware update. Non-Duo cards can be used, but it requires a bit of tinkering, and reduces the overall asthetic of the PSP.
The primary producers of Memory Stick media are Lexar, SanDisk and Sony.