Under its shiny new skin, new hardware and software, such as a slimmed down version of Apple's OS X operating system and a flashmemorydrive, instead of the current iPod's mechanical hard drive, could keep the new device thin and light.
The flashmemory in the Fusion Drive moves data and applications frequently accessed by the user to the flashmemory and move less frequently used data to the hard disk drive as the flashmemory becomes full.