In the gruelling three week Tour de France bicycle race, the green jersey goes to the rider who leads the points competition, usually a good sprinter. It was introduced in 1953; until then, the only special jersey was the yellow jersey, awarded to the rider with the least amount of accumulated time. The Tour organizers say the points jersey is green because it is the colour of hope, but it was actually red one year in honour of that year's jersey sponsor.
In 1975 two new jerseys were introduced: the polka-dot jersey for the King of the Mountains (best climber), and the white jersey for the best young rider.
All the jerseys are awarded each day, but the real victory is to wear the jersey on the last day of the race, on the podium in Paris. He who gets it there is the "real" green jersey winner for the year.
The earning of points in the green jersey competition is a bit complicated. There are four types of stages in the Tour: flat, semi-mountainous, mountainous, and individual time trials. For flat stages, the first 25 racers across the finish gain points, ranging from 35 points for the winner to 1 point for the 25th. (Note that the riders are also clocked across the line, but in the case of a pack of riders, all receive the same time as the leader as long as there is no daylight visible between their wheels. Only the points they receive will differ.) For the semi-mountainous stages, points range from 25 for the winner to 1 for the 20th; for mountainous, 20 for the winner and 1 for the 15th. During time trials, only the top ten going across get points, 15 for the winner and 1 for the tenth. In addition, most stages have two or three intermediate sprints along their length, which allow three riders to earn extra points: 6, 4, and 2 for first, second, and third respectively.
The record holder for the green jersey is Erik Zabel; he has held it six times, and in 2001 actually won it back on the last day of the race. The great Eddy Merckx won the green jersey three times, the only yellow jersey wearer to earn both jerseys in the same year (1969, 1971, and 1972). So great was Merckx that in 1969 he also held the polka-dot jersey, again the only rider ever to have done so.