1) It is easily interfaced as a peripheral to your arduino sensor shield module. 
2) Through programming, you can read and write to the SD card using your arduino. 
A. Can be used for SD Card more easily, such as for MP3 Player, MCU/ARM system control 
B. All SD SPI pins output, MOSI, SCK, MISO and CS. 
C. Support 5V/3.3V input.