If you want to use an optical drive with the late 2012 iMac, you will need to buy an external drive. This adds to the higher cost of the newer version of the iMac, and if you intend to add RAM past the standard 8GB, be sure to include this in your initial order since the new model is not user serviceable at all.
Like stated it doesn't have one, No Superdrive. But you do NOT have to buy an Apple superdrive to have a CD/DVD drive for your new iMac. Just buy an External CD/DVD drive that connects by USB, Tray load type is best, and it will work on your Mac. And it will be much cheaper then the Apple external, NOT SO, Suprdrive.