The luge competition consists of three events: men's, women's and doubles. Doubles teams are almost always two men.
Athletes take four singles runs or two doubles runs and the fastest total time is the winner.
The athletes travel feet first down the course in the luge (the French word for sled).
Men and women compete on the same track, but the women start from a position further down the course.
The sled rides along the course on two steel runners and can reach speeds of more than 90mph.
The skeleton event is similar to the luge but competitors travel on their stomach, head first, down the track.
The men's skeleton event is being held for the first time since the 1948 Games in St Moritz. Women's skeleton is making its Olympic debut.
Competitors do two runs on the same day with the final standings determined by the aggregate time of the two runs.