There are several classes of MMC, which are each designed for specific applications. Here are some examples:
Read Only Memory (ROM) MMC cards: the data content of these cards is fixed, but they are extremely practical and used in diverse applications spanning audiovisual to telecommunications.
Read/Write (RW) MMC cards:these cards are commonly used for quick and accessible mass storage. They can be flash, onetime programmable (OTP), or Multiple Time Programmable (MTP).
I/O MMC cards: these MMC cards are used for networking and communication applications and come with an additional Interface link.