Schematics : http://dn.odroid.com/eMMCModule/
eMMC Module Reader is included
You need the above eMMC Module Reader to update the OS of the eMMC Module. Transcend USB multi-slot SD Card reader in the below picture is not included.
More about the eMMC Module : http://odroid.com/dokuwiki/doku.php?id=en:emmc_reference_chart
You can boot from a MicroSD card or an eMMC module. The MicroSD interface supports the higher performance UHS-1 mode as well.
File access of a 512MB file (read/write) on three different storage options shows distinct performance differences.
The eMMC 5.0 storage is ~7x faster than the MicroSD Class-10 card in read tests. The MicroSD UHS-1 card is ~2x faster than the MicroSD Class-10 card in read tests. The MicroSD UHS-1 card provides a great low-cost option for many applications!