The MultiMediaCard (MMC) is a flash memory memory card standard. Unveiled in 1997 by Siemens AG and SanDisk, it is based on Toshiba's NAND-based flash memory, and is therefore much smaller than earlier systems based on Intel NOR-based memory such as CompactFlash. MMC is about the size of a postage stamp: 24 mm x 32 mm x 1.5 mm. MMC originally used a 1-bit serial interface, but newer versions of the specification allow transfers of 4 or sometimes even 8 bits at a time. They have been more or less superseded by Secure Digital cards, but still see significant use because MMC cards can be used in any device which supports SD cards.
Typically, an MMC card is used as storage media for a portable device, in a form that can easily be removed for access by a PC. For example, a digital camera would use an MMC card for storing image files. With an MMC reader (typically a small box that connects via USB or some other serial connection, although some can be found integrated into the computer itself), a user could copy the pictures taken with the digital camera off to his or her computer. Modern computers, both laptops and desktops, often have SD slots, which can read MMC cards.
MMC cards are currently available in sizes up to and including 8 GB, and are used in almost every context in which memory cards are used, like cellular phones, digital audio players, digital cameras and PDAs. Since the introduction of Secure Digital card few companies build MMC slots into their devices, but the slightly thinner, pin-compatible MMC cards can be used in almost any device that supports SD cards. An exception is some mobile devices like the Nokia 9300 communicator, where the smaller size of the MMC card is a benefit.
Multimedia Card (MMC) is a memory card based on FLASH technology. It is joint venture of SanDisk and SiemensAG and launched in 1997. It is one of the FLASH memory standards. Multimedia card uses NAND based flash memory offering smaller form factor (24 mm X 32 mm X 1.5 mm) compared to some other FLASH standards such as CompactFLASH. Multimedia card serves as a 1-bit serial interface as well as 4 and 8-bit parallel interface.

MMC form factors

The technology used in MMC is an open standard. So any company can enhance the product. Multimedia cards are available in a variety of form factors. These include RS-MMC (reduced size MMC), MMCmini, MMCmicro, MMC4x, MMCmobile, and secureMMC.
Multimedia cards like other memory cards such as Secure Digital (SD) cards and Smart Media cards are used in portable devices. Multimedia cards offer more storing capacity than Smart Media. MMCs are commonly used in digital cameras and video recorders. Modern PCs contain slots for these cards. MMC cards can be used with most SD card slots as well. Older PCs especially laptops and devices that do not contain such slots require a card reader. Other MMC uses include Personal Digital Assistant (PDA), Cell Phones, and digital audio players. Maximum storage capacity of multimedia card is 4 GB. On the whole MMC cards can be used in all the applications where memory cards are used.

The MultiMediaCard (MMC) is a flash memory memory card standard. Unveiled in 1997 by Siemens AG and SanDisk, it is based on Toshiba\'s NAND-based flash memory, and is therefore much smaller than earlier systems based on Intel NOR-based memory such as CompactFlash. MMC is about the size of a postage stamp: 24 mm x 32 mm x 1.5 mm. MMC originally used a 1-bit serial interface, but newer versions of the specification allow transfers of 4 or sometimes even 8 bits at a time. They have been more or less superseded by Secure Digital cards, but still see significant use because MMC cards can be used in any device which supports SD cards.
Typically, an MMC card is used as storage media for a portable device, in a form that can easily be removed for access by a PC. For example, a digital camera would use an MMC card for storing image files. With an MMC reader (typically a small box that connects via USB or some other serial connection, although some can be found integrated into the computer itself), a user could copy the pictures taken with the digital camera off to his or her computer. Modern computers, both laptops and desktops, often have SD slots, which can read MMC cards.
MMC cards are currently available in sizes up to and including 8 GB, and are used in almost every context in which memory cards are used, like cellular phones, digital audio players, digital cameras and PDAs. Since the introduction of Secure Digital card few companies build MMC slots into their devices, but the slightly thinner, pin-compatible MMC cards can be used in almost any device that supports SD cards. An exception is some mobile devices like the Nokia 9300 communicator, where the smaller size of the MMC card is a benefit.
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Handset to rise as the major demander for memory card

The anticipated camera phone shipment growth should continue to grow associated memory card demand. Card standards, which are now classify into certain major camps, are also deriving from their origins with more alternatives to feed the demand of shrinking handset sizes.
Camera phone has now overtaken digital camera's position as the largest demander of memory card. Shipment of camera phone should occupy over half of overall handsets at an approximate of 450mn units in 2006, versus the 80 million units shipment of digital camera, reflecting the associated substantial demand for memory card.
Among the current three major memory card standards, namely SD (Secure Digital), MMC (Multi-Media Card) and MS (Memory Stick), SD grabs a larger competitive edge over the others on leading handset vendors' support. Vendors including Nokia, Motorola, Samsung, LG and Siemens have all join the SD camp and roll out respective SD-supported handsets. The card standard of SD is jointly developed by the number one memory card seller SanDisk and Japan's Matsushita and Toshiba while related new standards and marketing are handled by SDA (SD Card Association).

SD cards are now offering a wide range of sizes like mini SD (20x21.5x1.4mm) and microSD (15x11x1mm) in order to feed the demand of handset size minimization. Likewise, the MMC camp has also rolled out MMCmini (18x24x1.4mm) and MMCmicro (14x12.1.1mm) while MS also offers MS Duo (20x31x1.6mm) and MS Micro (15x12.5x1.2mm).