Road biking has increased dramatically in the US in the past few years. Specifically these bikes are designed with 2 things in mind, speed and efficiency. They have narrower tires than the other categories of bikes and increased aerodynamics enabling a rider to cover long distances at higher speeds. Within road biking are a number of different styles, the most common is the race bike followed by time trial/tri bikes and touring bikes. The race bike design emphasizes low weight and aerodynamics whereas the touring bikes tend to have stronger (therefore heavier) frames and wheels, lower gearing, and a frame designed specifically to carry cargo utilizing panniers and other packs.  A new category of road bike is the comfort road, it comes in both recreational and performance grades.  It is best suited for special-event rides and riders looking for comfort and performance.

Burly

Cannondale

Colnago
Diamondback
Felt
Fuji
GT

K2
Klein