Courtesy of Cristiano Citton, 2-time Olympic cyclist (Atlanta 1996, Sydney 2000)
This is an outdoor, open-road race where large groups of riders race over varied terrain during single or multi-day events that go from point A to point B. The winner is the cyclist who completes the course in the shortest time. Road races can begin with either a mass start, where all the competitors start at the same time, or a staggered start determined by earlier time trials. The bicycles used for road racing are extremely light and responsive.
In professional road racing, the oldest and most prestigious races are referred to as the 3 Grand Tours -- the Tour de France, the Giro d'Italia (Tour of Italy) and the Vuelta a Espana (Tour of Spain). All 3 are multi-week races with daily stages. The stages are a mix of long, mass-start races, including both mountain and flat stages, as well as individual and team time trials.
On an amateur level, Gran Fondos are long-distance, mass-participation road-racing events where riders of all abilities can compete.
Track racing is divided into 2 categories: sprint and endurance. These races usually take place at a Velodrome, a specially built oval track with a smooth surface and steeply banked curves. A minimal kind of bike is used with 1 fixed gear and no brakes. Sprint races are generally between 3 and 8 laps in length with a focus on raw sprinting power and race tactics to defeat opponents. Endurance races are held over much longer distances, varying from 12 to 16 laps for individual and team pursuit races, and up to 200 laps in a World Championship or Olympic competition.