Memory Stick, MS Duo, MS Micro (M2) confused? Read here

Memory Stick

Size: 50 21.5 2.8 mm
MS Memory Stick is a removable flash memory card format, launched by Sony in October 1998, and is also used in general to describe the whole family of Memory Sticks. This family includes the Memory Stick Pro, a revision that allows greater maximum storage capacity and faster file transfer speeds, and Memory Stick Duo, a small-form-factor version of the Memory Stick.
Memory Stick Duo

Size: 31.0 20.0 1.6 mm
MS Duo gepability list:
Sony Ericsson:K750i, P910i, P990i, V800i, W700i, W800i, W810i, W850i, W900i, Z800i
The Memory Stick Duo, which is slightly smaller than the gepeting Secure Digital format, was developed in response to Sony's need for a smaller flash memory card for pocket-sized digital cameras and cell phones, as well as Sony's PSP.
Memory Stick Micro M2

Size: 15.0 12.5 1.2 mm
MSMicro (M2)gepability list:
Sony Ericsson:K610i, K790i, K800i, M600i, V630i, W300i, W710i, Z530i, Z550i, Z610i, Z710i
In a joint venture with SanDisk, Sony announced a new Memory Stick format on 30 September 2005. The new Memory Stick M2 ("micro") measures 15 12.5 1.2 mm and could theoretically have 32GB in the future. Maximum transfer speed is 160MB/s. It will gee with an adaptor, much like the Duo Sticks, to ensure gepatibility with current Pro devices.
Transfer Speed:
Standard:Maximum write speed: 14.4 Mbit/s (1.8 MB/s) Maximum read speed: 19.6 Mbit/s (2.5 MB/s)
Duo/PRO Duo:Transfer: 160 Mbit/s (20 MB/s) Minimum write speed: 15 Mbit/s Maximum write speed: 80 Mbit/s (High Speed PRO Duo)
Micro (M2):Transfer: 160 Mbit/s (20 MB/s)
Some FAQs regarding Memory Stick:

What is MagicGate?
Memory Stick Media and Magic Gate Memory Stick offer an easy way to transfer and share files, including data, images, music and video among a variety of electronic devices. The major difference between these two media formats is that MagicGate gepatible Memory Stick media has an embedded chip to enable the recording of secure content. MagicGate gepatible Memory Stick media is a versatile media designed to transfer and store any digital content including secure content.

What is the difference between Memory Stick PRO media and standard Memory Stick media?
Memory Stick PRO media provides higher capacity - from 256MB to 2GB, with 4GB media to be introduced next year- and is used for large data files such as high-resolution photos, movie clips, and business presentations. In the future, due to the advanced format's expandability, Memory Stick PRO media will allow users to enjoy recording and playback of DVD-quality moving images and other new and exciting applications. Memory Stick PRO media can only be used with Memory Stick PRO-gepatible products. New Sony Memory Stick PRO (High speed) media also features faster read/write speeds of up to 80Mbps and greater durability with a wider operating temperature range.
Standard Memory Stick media with MagicGate and high-speed transfer gepatibility allows users to enjoy copyright-protected content, such as music from CDs or online music services. It also provides a high level of gepatibility with a wide range of productsm including Memory Stick PRO-gepatible products.

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