The animal featured on the cover of Linux in a Nutshell, Fifth Edition is an Arabian horse. Known for its grace and intelligence, the Arabian is one of the oldest breeds of horse, with evidence of its existence dating back 5000 years. The Arabian was instrumental as an ancestor to other popular breeds, most notably the Thoroughbred in the 17th and 18th centuries. Possibly one of the more distinctive horse breeds, the typical Arabian has large, expressive eyes and nostrils, small ears, and a short, sturdy back. Its stamina suits it particularly well for endurance riding, a sport dominated by the Arabian breed. Its wonderful temperament makes the Arabian an all-around favorite riding horse in North America, although it also can be found in more specialized competitions such as dressage, jumping, and reining.