Road cycling is the most widespread form of cycling in which cyclists ride on paved roadways. It includes recreational, racing, commuting, and utility cycling. As users of the road, road cyclists are generally expected to obey the same laws as motorists, however there are certain exceptions. While there are many types of bicycles that are used on the roads such as BMX, recumbents, racing, touring and utility bicycles, dedicated road bicycles have specific characteristics that make them ideal for the sport. Road bicycles generally have thinner tires, lighter frames with no suspension, and a set of drop handle bars to allow riders to get in a more aerodynamic position while cycling at higher speeds. On a flat road, an intermediate cyclist can average about 18 to 20 mph, while a professional rider can average up to 25 mph. At higher speeds, wind resistance becomes an important factor; aerodynamic road bikes have been developed over the years to ensure that as much as possible of the rider's energy is spent propelling the bike forward.