Bobsleigh has been contested at every Olympic Winter Games apart from Squaw Valley 1960, when the prohibitive cost of building a track was ruled out by organisers.
The two-man competition was introduced at Lake Placid 1932 and women made their debut at Salt Lake City 2002.
Germany are the most successful nation in Olympic history with ten golds, though Switzerland have claimed more medals.
Great Britain won silver in the four-man event at the inaugural Games in Chamonix in 1924 and followed up with bronze 12 years later in Garmisch-Partenkirchen.
Nearly three decades passed before a British athlete returned to the podium when Tony Nash and Robin Dixon won a famous gold at Innsbruck 1964 – their winning margin just 0.12 seconds over the Italian favourites.
Another 30 years passed before Team GB’s next success at Nagano 1998, pilot Sean Olsson and crew Dean Ward, Courtney Rumbolt and Paul Attwood securing a share of bronze with France.
Bobsleigh teams include a brakeman and a pilot in the two-man and two-woman events while two crewmen or pushers are added for the four-man race.
From a standing start, the crew pushes the sled in unison up to 50 metres, with speeds in excess of 25mph recorded before the crew even loads into the sled.
Athletes need strong nerves and a good sense of balance with pilots trained to develop an eye and touch for steering.
With the start so important, many crew members graduate from track and field although five-time Olympic champion rower Sir Steve Redgrave spent two seasons on the British team in the early 1990s.
Bobsleigh events are staged over two days, with two runs staged on each day. The four runs are timed to 0.01 seconds and the fastest total time determines the medallists and finishing positions.
If two teams complete the competition in a tie, they are awarded the same place. The starting order for the first run is considered crucial, with a definite advantage to being among the first down the track while the ice is still fresh.
World rankings are used to give the top ranked sliders the benefit of an early start number. For the second run, the competitors start in reverse order of their time from the first run.
There are two groups: the fastest 20 from the first run are in the first group, again giving them the benefit of optimum conditions.
In the first group, the slowest competitors go first and the fastest competitor goes last. In the second group, the fastest competitor goes first, i.e. 21st down the track.
Strict rules govern the weight of sled and crew with all equipment carefully inspected by officials before each run.