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.
A Chromebook is a laptop running the Linux-based Chrome OS as its operating system. The devices were originally designed to be used primarily while connected to the Internet, with most applications and data residing in the cloud. The original Chromebook was an example of a thin client.