Gallery: Tour de France beginners' guide

Isle of Man-born Mark Cavendish won two of the first three stages in this year's race. So why isn't he in contention to win the Tour? The key is that Cavendish is a specialist sprinter. He's not a multi-discipline rider capable of winning time-trials or mountain stages, which are always part of the Tour's itinerary. Only strong all-rounders like Lance Armstrong or Alberto Contador are capable of winning the Tour de France. But put them next to Cav in a sprint, and he'll beat them every time.

So why enter a race you can't win? In this year's Tour, Cavendish's stated aim is to get to Paris, but he's also going after the green jersey. If he's wearing the green jersey in Paris, Cavendish has won his own part of the Tour. Riders can accumulate points for this with stage placings. For example, the winner of Stage 10 gets 35 points. Riders can also win points for intermediate sprints, which are races to a point within each stage. After grabbing the green jersey on Stage 2, Cav turned all green, including the shoes above - before Norwegian rider Thor Hushovd overtook him in the points standings.

The coveted yellow jersey is worn each day by the leader of the race. Fabian Cancellara won the opening time-trial in Monaco, and held it by a fraction of a second from Lance Armstrong after the team time trial in Montpellier on Stage 3. He's highly unlikely to win the Tour de France because when it comes to the mountain stages, there are far stronger riders than him. Rinaldo Nocentini currently holds the jersey, but he has no chance of winning the Tour. The main contenders are happy to let him lead the race at the moment. You might say it's a marathon, not a sprint - except a marathon is 26miles and the Tour is about 2,100m this year.

The King of the Mountains: arguably the coolest jersey both in name and design. In most stages there will be categorised climbs, where riders can win points in the KOM competition. First over the top of the mountain gets the most points: simple. Whoever's topping the KOM table gets to wear the polka-dot jersey - Egoi Martinez of Euskaltel-Euskadi doesn't look to happy about it here, but we're sure he's smiling on the inside.

Yet another classification within the Tour de France is the competition for best young rider, indicated by the white jersey. Roman Kreuziger of Liquigas is pictured here after Stage 2 of this year's race, between Monaco and Brignoles. The white jersey is another race within the race. Any rider who was under 25 on January 1 in the year of the race qualifies. A good while since Lance Armstrong was in the running for it, then.

Sprinters can't win stages on their own: they need the support of other team members to put them in position to win a sprint finish. Team Columbia's Mark Renshaw (pictured) and Michael Rogers are regarded as some of the best lead-out men in the world. They protect team-mate Mark Cavendish's position in the peloton and allow the sprinter to ride in their slipstream before he bolts for the finish line. Rogers classed Cavendish's Stage 3 win as "the best team effort I've been a part of since 10 years as a pro".