Originally, Alberto Contador was awarded the yellow jersey in 2011, but it was taken away due to him doping in the race. The yellow jersey was then given to runner up Andy Schleck.
The yellow jersey
A yellow jersey is the yellow-coloured shirt worn by the leader of a cycling race at a certain time during the Tour de France.
Cycling Tour de France to be specific
Yellow, green, polka dot..?
Greg Lamond
He is the head of the race who everyone follows
Tour De france
Last year's Winner gets to start in the yellow jersey, if he is doing the race.
Mark Cavendish
The famous race that awards the winner of the race the yellow jersey is the Tour de France. The person with the fastest time to the finish is awarded with the honorable yellow jersey.
Canada's Alex Stieda was the first North American to wear the yellow jersey, on Stage 2 of the 1986 Tour de France.
Le Tour de France isn't raced by athletes representing countries, it's raced by professional teams, usually assembled with riders from several different nations. The yellow jersey is worn by the rider with the overall shortest time.