Match races between two sailing yachts. One yacht, known as the defender, represents the yacht club that currently holds the America's Cup and the second yacht, known as the challenger, represents the yacht club that is challenging for the cup. The timing of each match is determined by an agreement between the defender and the challenger. The America's Cup is the oldest international sporting trophy.

History:
In an 1851 53-nautical-mile race around Isle of Wight in the south coast of England, the 101 ft schooner America, representing the young New York Yacht Club, would go on to beat the best the British could offer and win the Royal Yacht Squadron's 100 Pound Cup.
It became known as America's Cup.

The very first challenge would come from British railway tycoon James Ashbury, who raced against a fleet from the New York Yacht Club just off Staten Island in 1870. After much dispute over the conditions for racing, Ashbury's Cambria finished tenth in the 17-boat fleet, prompting a second challenge the following year.

After reportedly consulting his lawyers, Ashbury insisted on racing against just one boat, not an entire fleet and protested both the scoring of the races and the Race Committee who set the race course.

The next two Challenges came from Canada, but the northerners were no match for the Americans and were soundly beaten.

Any yacht club that meets the requirements specified in the Deed of Gift has the right to challenge the yacht club that holds the Cup.
From 1870 to 1970 there were 20 challenges all won by the New York Yacht Club.

Club	Years	Record
New York Yacht Club	1851-1983	24-1
Royal Perth Yacht Club	1983-1987	1-1
San Diego Yacht Club	1987-1995	3-1
Royal New Zealand Yacht Squadron	1995-2003	2-1
Société Nautique de Genève	2003-2010	2-1
Golden Gate Yacht Club	2010-	2-0

Races were moved from New York City to Newport in 1930.
Races were held on a 30 mile course at the mouth of Narragansett Bay off Breton Reef in the Atlantic Ocean.
At the same time it was changed from the best 3 out of to the best 4 out of 7.

There was a 21 year halt in America's Cup competition from 1937 to 1958.
Racing continued with a new class of racers, 12 Meters (39 ft).
The course was shortened to 24 miles.

In 1970, more than one yacht club interested in challenging for the America's Cup, so for the first time, a competition was staged to determine the single Challenger that would face the Defender, the New York Yacht Club (NYYC).

The French malletier Louis Vuitton became involved with the America's Cup in 1983, supporting the Challenger Selection Series that came to be known as the Louis Vuitton Cup.

America lost to the Royal Perth Yacht Club in 1983.
The San Diego Yacht Club with Dennis Connor won it back in 1987.
They defended in 1988 with a controversial wing-masted catamaran vs Australia's 90' monohull.
There were several court battles to determine the results.

In 1992 the International Americas Cup Class (IACC) was developed for the America's Cup between 1992 and 2007. Length was limited to 25 m (82 ft).

New Zealand won in 1995 and successfully defended in 2000.
Switzerland won in 2003 and successfully defended in 2007.

In 2010 gigantic, specialized multi-hull racing yachts were used.
The U.S. (Golden Gate Yacht Club (GGYC) - BMW Oracle Racing team [Larry Ellison]) won.

The 2013 race was marked by tragedy when Andrew "Bart" Simpson, 36, was killed when he was trapped under the wreckage of the Artemis Racing (representing the Royal Swedish Yacht Club) sailboat that capsized during a training run.

Oracle Team USA is the defender of the 35th America's Cup. It is scheduled to take place sometime during 2017. Protocol for the 35th America's Cup is currently being negotiated with the Challenger of Record, Team Australia and the Hamilton Island Yacht Club.

The venue search for the 35th AmericaÕs Cup has narrowed the finalists to Bermuda, Chicago and San Diego. San Diego plans to set the course in the bay for easy viewing. They would use AC62 boats. - See 2014 article at

People:
Ted Turner, who had competed in the Olympic sailing trials in 1964, bought the pervious winner, Courageous which he skippered and won in 1977.

Larry Ellison Oracle co-founder and CEO and billionaire. Funded the America's cup team which beat Switzerland in 2010.
He along with Russell Coutts were on the crew in 2010 but because of the physical demands of the 2013 boats they will watch from a chase boat.

Dennis Conner has won the America's Cup four times, successfully defending the Cup in 1974 (Courageous), 1980 (Freedom), loosing in 1983, winning as the challenger in 1987 (San Diego Yacht Club - Stars & Stripes) and defending in 1988 (Stars & Stripes H3 A wing-masted catamaran vs a 90' monohull).
Conner is credited for taking the sport from an amateur sport to a professional level.

James Spithill is an Australian yachtsman. He debuted in the America's Cup in 2000 with Young Australia. In 2010, as skipper and helmsman for BMW Oracle Racing, Spithill became the youngest ever winner of the America's Cup as skipper of Oracle Team USA.

Russell Coutts is a competitive sailor from New Zealand. He holds an impressive record in the America's Cup, with 16 wins and no losses since 1995 winning four America's Cups (1995 (New Zealand), 2000 (New Zealand), 2003 (Switzerland), 2010 (U.S. CEO of Oracle Team USA).

Ben Ainslie, UK - The most successful sailor in Olympic history, with 5 golds.

Herreshoff Marine Museum & America's Cup Hall of Fame

Boats:
Original America's Cup racing boats had to be large vessels that were capable of crossing the Atlantic Ocean. After World War II, the vast fortunes needed to finance these huge boats had largely vanished on both sides of the Atlantic and the 12 meter (39 ft) yachts era began.  

Year	LWL ft	type	Race length
1851	101	schooner	53 mi
1881	85	schooner	53
1887		sloop	53
1901		sloop	40*
1930	80-87	J Class sloop
1958	39 12 m	sloop	24 mi
1988	60	Catamaran1
1992	82	IACC2
2010	90	IACC Trimaran
2013	72	AC72 catamaran	3 mi

* Around 1900 races consisted of:
1st and 3rd race 40 miles (20 windward and 20 leward)
2nd race A equilateral triangle course with a total of 39 miles.

1. In 1987 New Zealand challenged with a 132 ft design and Dennis Conner didn't have time to come up with a conventional design to compete so used a 60 ft catamaran, which was allowed under the rules, and won despite a court controversy.
2. IACC - International America's Cup Class - 25 meteres

LWL - Waterline Length
Early boats displacement ranged from 79 - 274 tons. J-Class boats (1930's) were 128-162 tons. The 12 meter yachts introduced in 1958 had a displacement of 20-25 tons.
The AC72 catamarans used in 2013 had a displacement of 6.5 tons, but sailed on hydrofoils most of the time.

See Challengers and defenders

2013:

Source: Bloomberg.com

Oracle Team USA, the defender and Emirates Team New Zealand, winners of the Louis Vuitton Challenger Cup met in the finals from September 7 - 25, 2013.

In 2013 new class AC-72 (72 ft. wing-sail catamarans) were used in a best 9 of 17 races in San Francisco Bay.
These boats which can cost up to $10 million in research, development, materials and construction. It can cost more than $100 million total to mount a challenge. Some estimates for Oracle's total expense for the 2013 defense were $156 Million. This limited competition to only 3 challengers (Artemis [Sweden], Luna Rossa [Italy], Emirates New Zealand) instead of 10 to 15 in the past.
The racecourse includes 5 legs over a 3 mile course.
They will cover 10 nautical miles in about 25 minutes.

The AC72 (America's Cup 72 class) is a wing sail catamaran with a 72 ft waterline length and a 131 ft high solid wing with a pivot in the middle as a main sail. They can hit 44 knots (50 MPH) while the hull is out of the water up on foils.
Foils are L-shaped boards which can be extended under each hull (2 per hull), to reduce drag and increase speed.
The AC 72 was the idea of Larry Ellison and Russell Coutts.

Teams: Crews are limited to 11 sailors

Position	Oracle USA	Emirates NZ
Skipper/Helsman	James Spithill, Aus	Dean Barker, NZ
Tactician	John Kostecki, US Ben Ainslie *, UK	Ray Davies, NZ
Strategist	Tom Slingsby, Aus	Adam Beashel
Wing Trimmer	Kyle Langford, Aus Murray Jones, NZ	Glenn Ashby Grant Loretz
Jib Trimmer	Joe Newton, Aus	James Dagg
CEO/GM	Russell Coutts, NZ	Grant Dalton, NZ
Main Backer	Larry Ellison, US	Matteo de Nora, SW-IT
Sponsoring Club	Golden Gate Yacht Club	Royal New Zealand Yacht Squadron

* Sir Ben Ainslie replaced John Kostecki (US) as tactician for the struggling America's Cup champion Oracle Team USA. The move had been expected since Kostecki called for a foiling tack that cost the American syndicate the lead in a punishing loss to Emirates Team New Zealand in Race 5

Larry Ellison, Oracle CEO and billionaire put together an international team with Australian James Spithill as helmsman/skipper and New Zelander Russle Coutts with 16 wins and no losses since 1995 winning four America's Cups [1995 (New Zealand), 2000 (New Zealand), 2003 (Switzerland), 2010 (U.S. CEO of Oracle Team USA) as CEO and 5 time British sailing olympian Sir Ben Ainsley as tactician.
There was only 1 American, Off-side trimmer Rome Kirby, on the boat for Team Oracle USA after Kostecki was replaced.

USA started with a 2 race penalty because of a rule violation and at one point were down 8 to 1, with only 9 races required to take the cup.

The Kiwis had perfected upwind foiling, which Oracle was not doing because it required a larger (lower) angle against the wind to get the necessary speed, but this increased distance.
Oracle called a timeout and figured out they could get to the upwind mark faster by traveling a longer distance but faster on foils.
Oracle also removed an extra pole called a spine in high winds, which was there for an extra sail in low winds.

Then there was the matter of luck. Twice during this event, New Zealand had a commanding lead in a race - only for it to be called off. The first time was a result of high winds that exceeded the strict limits. The second time in low winds when they couldn't finish within the 40-minute time limit.

The wind limit (actually a combination of wind and tide) was lowered to 23 knots after Sweden's Artemis Racing suffered a disastrous accident during practice in May, when its boat broke apart and capsized, killing British Olympian Andrew "Bart" Simpson.

New Zeland developed a lot of techniques copied by other teams.
Foils, Roll tacking, foil tacking,

See:
America's Cup: How Oracle Saved the Cup - WSJ.com
Pictures
Video - Salt Water Flying Machines in San Francisco - WSJ.com