The C horizon is below the A and B horizons of most soils. It consists of materials that were little altered by the soil-forming processes, though the materials may be modified by weathering. Below the C horizon in some soils is an R horizon of consolidated bedrock, such as limestone, shale, or sandstone.
Ultrabooks Guide. If you want one of the most portable computers on the market, consider getting an Ultrabook, a new kind of super-thin, ultra-light laptop that wakes from sleep quickly and offers a compelling Windows 8 experience.
(Oh and the screen is pretty awesome, the number of devices are cool and it's pretty darn light for all of it's power too) I've been using the Ultrabook as my primary travel device for most of the summer, and what it's done is convince me that when someone releases a consumer grade Haswell ultrabook, I'm buying.