RS-MMC is a type of removable flash memory card. Like any flash memory card, it can be used to store various types of files, including photos, videos, music, or software.
There are two different types of slots for RS-MMC cards: 3-volt and 1.8-volt. Although they operate at different voltages, they are physically identical, so users need to be careful to use the right type of card.
Traditional, older RS-MMC cards and slots are 3-volt. Some newer phones have 1.8-volt slots, and therefore require 1.8-volt or dual-voltage cards.
MMCmobile cards are dual-voltage RS-MMC cards.
RS-MMC is similar to the MMC format, but smaller.
RS-MMC is smaller than MMC and SD, but larger than TransFlash. RS-MMC is close in size to the competing miniSD format.