Along with the green jersey, the yellow jersey, and the polka-dot jersey, one of the four prizes given out at the end of every stage of the Tour de France.

The white jersey was introduced in 1968. Originally, it was given to the leader in the combination classification of the Tour de France. The combination classification was, as the name suggests, a combination of the other ranking systems for the tour: General, mountains, and points.

In 1975, the white jersey changed from the combination classification award to its current form, the Best Young Rider award. Before 1975, the competition was open to all racers, but with the change to Best Young Rider came a change in qualifications: only riders aged 25 years or less could compete for it. From 1983 to 1986, the jersey was available only to those riders who were racing in the tour for the first time, though the original system was restored in 1987.

During the late eighties, the Societe du Tour de France, the organizing body of the Tour, decided to simplify the 2100-mile race. In 1989, the white, red, and combination jersey were eliminated, leaving only the 3 major prizes.

The white jersey made its return for the 2000 tour. It retained the original Best Young Rider award system from the 1975 revision, but the competition for the jersey was renamed to Souvenir Fabio Casartelli to honor an Italian rider, Fabio Casartelli, who fatally crashed during the 1995 tour.

The white jersey is currently sponsered by Aquarel.

Jan Ullrich has held the white jersey after the last day of racing three times (1996, 1997, 1998), the most times of any rider. Marco Pantani holds second place for total wins with two, in 1994 and 1995.


Mad noder props to Linca for corrections.
Sources:
1 - http://www.angelfire.com/realm/cvccbikers/tour/eddy/white.htm
2 - http://www.angelfire.com/realm/cvccbikers/tour/eddy/other.htm
3 - Google cache of www.bicycling.com/tdf2001/beginners/
4 - http://www.letour.fr/2002/us/infos/enjeux.html