The UCI world championships are annual competitions promoted by the Union Cycliste Internationale (UCI) to determine world champion cyclists. They are held in several different styles of racing, in a different country each year. Championship winners wear a white jersey with coloured bands around the chest for the following year. The similarity to the colours of a rainbow gives them the colloquial name of "the rainbow jersey." The first three individuals or teams in each championship win gold, silver and bronze medals. Former world champions are allowed to wear a trim to their collar and sleeves in the same pattern as the rainbow jersey.