As their namesake would suggest, these bikes handle best and are designed to be ridden on the road, ideally smooth pavement. They generally have skinny tires and drop (curved) bars that offer a wider range of hand positions. Some road bikes are more aerodynamic than others, some are designed for racing, and others are designed with endurance in mind. Regardless of design, if you are a rider looking to put in longer miles (greater than 15) on the road, especially with climbs and descents, a road bike is the choice for you.
These are a special type of ‘road’ bike designed to maximize aerodynamics. Essentially, this type of bike works to minimize wind resistance through an aerodynamic geometry and “aero bars” that allows the rider to be more forward and low on his/her forearms. These bikes are most suited in races where the rider will be starting alone or in a staggered start, such as triathlon or time trial races. Because these are designed to go as fast as possible in a straight line, they generally do not handle as well as a traditional road bike.
A touring bike is a type of road bike that is designed to be more durable on long distance rides. Touring bikes will look like road bikes but typically are more relaxed to maintain comfort over the long distances. Touring bikes will have all mount points for front and rear racks as well as fenders. Those doing long distance tours will easily load their bike to weigh in at 100 lbs. Touring bikes can also double as great commuter bikes if you are a person needing to carry a lot of gear, but not wanting to do so on your body but rather on your bike.