The function of a Weyr is to fight Thread, an organism that originates in the Oort cloud of the Rukbat solar system, carried by a red planet with a loose elliptical orbit. The time during which Thread falls is called a Pass. These Passes last about 50 years, usually with a break of 200 years between.
A Weyr is headed by a Weyrwoman (rider of the most senior gold dragon) and a Weyrleader (the Weyrwoman's mate). A Weyr possess five types of dragons:
Bronze dragons are the traditional mates of the queens, and the rarest type of male dragon.
Blues and browns are the mates of the greens, and are more common than bronzes.
Staff in a Weyr include the Dragonhealer, responsible for the care of injured dragons, the Weyrharper, responsible for the entertainment of dragonriders during their off-duty hours, a Headwoman, who controls the cooking and cleaning staff, a Healer, who takes care of the humans in a Weyr, and various others.