The MultiMediaCard (MMC) is a flash memory memory card standard. MMC is about the size of a postage stamp: 24 mm x 32 mm x 1.4 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 They have been more or less superseded by Secure Digital cards (SD card), but still see significant use because MMCs can be used in most devices which support SD cards and they are cheaper than SD cards.