Prince William and his bride Kate overcame any wedding nerves as they sailed through their marriage ceremony with a polished, well-rehearsed and regal performance.
William has in the past compared the couple to a pair of ducks - calm on the surface but with little feet paddling away furiously beneath the water.
That spirit seemed in evidence as they calmly got through their vows with 1,900 guests watching on in Westminster Abbey, including all the senior royals and several foreign leaders, not to mention billions watching worldwide.
Having waved to the crowds lining The Mall in front of Buckingham Palace, William and his best man, brother Prince Harry, seemed in jovial mood as they arrived at the abbey.
Plain old Kate Middleton, as she was then, drew huge cheers as she drove from her hotel through the London streets.
Steadily guided by her father Michael, she walked slowly and calmly up the aisle ready for the eagerly-awaited ceremony to begin.
Harry, rocking on his feet in his military uniform from the Blues and Royals regiment, turned to look as they made their way through the choir towards the altar.
When Kate arrived at her groom's side, William turned to greet his bride and appeared to say "you look beautiful" before the congregation launched straight into the hymn "Guide me, O thou great Redeemer".
They stood just five steps away from where the coffin of William's mother Diana, princess of Wales was placed at her funeral in 1997.
William sounded nervous when he spoke for the first time to say "I will".
As Kate said her vows in a quiet voice, William seemed to be fighting back a smile.
With the service relayed to the crowds outside the abbey, huge cheers erupted each time they spoke.
Back inside the abbey, Kate slightly swallowed one of William's middle names, Arthur. However, garbling a royal groom's lengthy names is a British royal tradition, with Diana getting Prince Charles's in the wrong order at their wedding in 1981.
When William put the ring on Kate's finger, he struggled at the knuckle despite his steady hands.
The Archbishop of Canterbury, Rowan Williams, seemed very comfortable as he read through the marriage service.
When he pronounced them man and wife, the thousands gathered outside the abbey, some of whom had camped out for days, roared their approval with a huge cheer that was audible inside the church.
At the second hymn, British Deputy Prime Minister Nick Clegg sang much of "Love divine, all loves excelling" from memory, though his Spanish wife needed to read through the order of service.
The bride's brother James Middleton read the lesson, a section from Romans chapter 12, in a slow and purposeful delivery.
Richard Chartres, the Bishop of London, began his sermon with a flourish, quoting St Catherine of Siena, whose festival day coincides with the wedding.
The bishop was in his element as he spoke from the pulpit towards the newlywed couple, telling them: "This is a joyful day."
William was listening intently, but his concentration was broken while the Duchess of Cambridge, as Kate will be known with her new title, exchanged a cheeky glance with him, a smile breaking across William's lips.
But by that point, they had been man and wife for only a matter of minutes and could be forgiven letting the joy of the moment break through.
Prince William and Kate Middleton exchanged wedding vows at Westminster Abbey on Friday and were pronounced man and wife by the Archbishop of Canterbury Rowan Williams.
The second in line to the throne and his commoner bride were watched by 1,900 guests in the abbey and a global television audience of two billion.
Thousands of people spent a chilly night outdoors to secure a front-row view of a day rich in royal pageantry, as Britain hosted its biggest party since the late princess Diana married William's father Prince Charles in 1981.
Diana's absence was keenly felt throughout the day. Under a black and white front-page photograph of William and Kate and a smaller photograph of the late princess, the headline in The Sun newspaper said: "Mum would be so proud".
Prince William was made the Duke of Cambridge on his wedding day on Friday by Queen Elizabeth II and Kate Middleton will become the Duchess of Cambridge once they are married, Buckingham Palace said.
More than 5,000 police are on duty in the capital as crowds line the route from Buckingham Palace to Westminster Abbey.
Wedding dress by Sarah Burton
Kate Middleton's ivory and lace wedding dress was designed by Sarah Burton, creative director at the fashion house Alexander McQueen, the palace announced Friday.
As a smiling Kate entered Westminster Abbey to meet Prince William, officials confirmed long speculation that Burton had made her dress. They had previously refused to give even the slightest detail about it.
"Miss Middleton wished for her dress to combine tradition and modernity with the artistic vision that characterises Alexander McQueen's work," officials said in a statement.
"Miss Middleton worked closely with Sarah Burton in formulating the design of her dress."
They said the dress made with ivory and white satin gazar, with a train measuring 2.7 metres (8.8 feet) and lace sleeves, "eipitomises timeless British craftsmanship".
The bride had also borrowed a tiara loaned to her by Prince William's grandmother, Queen Elizabeth II.
Burton took over as creative director at the label after McQueen committed suicide in February 2010. She had previously worked side by side with him for 14 years.
The 36-year-old graduate of Central St Martin's had long been tipped as the wedding dress designer.
A woman wearing a studded leather belt doubled through the loops of her jeans, in a fashion identical to the one favoured by Burton, was photographed on Thursday evening slipping into the Goring Hotel where Kate was staying.
Her head was hidden under a huge fur hat in an attempt to avoid identification.
The dress is expected to spawn a thousand reproductions.
Elizabeth Emanuel, who created Diana's fairytale wedding gown in 1981 with her husband David, is still being asked to make copies of that gown, an ivory silk taffeta frock with a 25-foot (7.6-metre) long train.
"Exactly as it happened in 1981, there are going to be people watching as she walks down the aisle with their sketch pads, with the machinists and pattern cutters all ready and waiting. By the next morning you'll see copies in the high street," Emanuel said.
Diamond hair pin gift
Sri Lanka has gifted a Ceylon Sapphire studded diamond hair pin to Kate Middleton who marries Britain's Prince William on Friday.
The state-owned Sri Lanka Gem and Jewellery Authority (SLGJA) said the gift was in appreciation of the British Royal family's association with Ceylon Sapphires over many generations, Indian Express said.
“This is the first ever international campaign aimed at raising awareness about the rarity and value of the Ceylon Sapphire,” Macky Hashim, the SLGJA chief, said. The hair pin had already been delivered to the Middletons, Hashim said.
Kate Middleton already wears a blue Ceylon Sapphire engagement ring, coming from the late Princess Diana, the mother of the groom, Prince William.
Diana wore it for her own engagement in 1981.
Hashim said sales of Ceylon Sapphire replica rings were in big demand since the announcement of the Royal wedding.
From across the world
They came from all over the world, wearing outlandish outfits and waving Union Jack flags, rising before dawn or camping overnight to secure their spot for the royal wedding.
Thousands of royal enthusiasts braved a chilly night on London's streets to get a front-row seat for Prince William and Kate Middleton's wedding, their numbers swelled Friday by a constant stream of new arrivals.
"I might never have another opportunity to see such a thing," said Isabel Minguez, an 18-year-old student from Madrid sitting outside Westminster Abbey, where the couple will finally tie the knot after an eight-year courtship.
"I could have watched it on TV but up close it is so much better. And you meet people too," said Haytham Khalaf, a 35-year-old university researcher from Jordan, adding that the wedding was a "once in a lifetime" event.
The crowds were the biggest on The Mall, the wide tree-lined avenue leading to Buckingham Palace down which the newlyweds will travel in a horse-drawn carriage after the ceremony.
They will appear for the first time as husband and wife on the palace balcony, and are expected to treat the crowds to a kiss.
Australian Sam Harburg, 27, dressed in a a pink tie and dark blue jacket, arrived with a friend at 4:00 am equipped with a cool box with beer and two bottles of champagne, "one for the procession and one for the royal kiss".
After living in London, he was due to go home this weekend but pushed back his flight so he could join the celebrations. "I can tell my friends in Australia that I was here," he said.
The palace balcony doors opened at one point, sending a roar of excitement across the crowd -- at least those who could see.
"It's hard for short people. I can't see anything!" said Maria Read, 43, standing on a small but very unstable folding chair.
She said her family back home in Brazil had set their alarms for dawn to watch the wedding on television, saying: "We find it beautiful - it's their wedding but we celebrate it, we are part of the party."
The crowd was a riot of colour -- there were little girls in princess dresses, women sporting paper crowns and plastic tiaras, men in William paper masks and millions upon millions of red, white and blue Union Jack flags.
One couple came dressed as daffodils, the national flower of Wales, where William and Kate will live after their marriage, while two women wore wedding dresses with signs on their backs saying "It should have been me!".
Outside Westminster Abbey, Kim Ratcliffe, 37, wore a spectacular hat ontop of her blond hair. "I came prepared just in case they would invite me in!" she said, pushing her two daughters, both dressed as princesses, in their pram.
She came over from Texas with her British husband to watch the wedding, saying: "We love the monarchy -- it is part of history."
People have been camping outside the abbey since Monday night, but the excitement was mounting just hours before the ceremony. After an uncomfortable night, campers exchanged coffee and cakes before putting away their tents.
Back on The Mall, Julie Officer, a 39-year-old nurse from London, had donned a fancy hat similar to those worn by the royal family.
She arrived at 3:30am, while it was still dark, but found many hundreds had got there before her. "I wanted to see the balcony but it's already crowded," she said, wrapped in a sleeping bag alongside a security barrier.
Next to her was Bernadette Baker, also a nurse, from New York. "I am so curious to see what Kate does with her hair," said the 31-year-old, wearing a hat with purple flowers and a purple dress, and waving a Union Jack flag.
About 5,500 street parties are expected across Britain on Friday, including in the Scottish university of St Andrews, where William and Kate met.
In Bucklebury, the village where Kate grew up up west of London, marquees were set up on the green for a huge party with a hog roast, stalls and games as residents put on a big show for their most famous daughter.
No rush for throne
Prince William's wedding Friday is the next step in his journey to becoming king, but Princess Diana's eldest son has taken his time in getting married, and neither is he in any rush to take the throne.
William has overcome the tragedy of his mother's death when he was 15 to become the great hope of the British royal family in the 21st century.
Opinion polls show a majority of the public want the 28-year-old to leapfrog his father Prince Charles in the order of succession and take the throne after Queen Elizabeth II.
But such a move is highly unlikely and in any case, William has given no indication that he wants it anytime soon.
"Prince William wouldn't thank you for making him king tomorrow or next year," said Andrew Morton, whose book on Diana in 1992 revealed the extent of her loveless marriage to Charles.
"Because everything he stands for is to live his life as normally as possible and to escape the steel trap of being head of state."
It was Diana's wish that her sons lead as normal lives as possible, unlike his father Charles, who is steeped in tradition and surrounded by butlers and aides.
"William cooks for himself, he makes his own bed. He behaves like a normal person and he seems to relish that," said royal author Penny Junor.
Born on June 21, 1982, seven days after the end of Falklands war ended, William, and his younger brother Harry, enjoyed a childhood infused with their mother's sense of fun and a warmth that was lacking in their fathers.
But William became his mother's shoulder to cry on as his parents' marriage disintegrated in public, and then when Diana died, he had to grieve in the eyes of the world.
He and Harry walked behind their mother's coffin through the streets of London for the funeral in Westminster Abbey, the venue for William's wedding Friday.
Ironically, it was Diana's death in Paris in 1997 as her car was chased by photographers that allowed William to grow up relatively undisturbed by Britain's voracious tabloid press.
Charles struck a deal with newspaper editors under which his sons were left in peace in return for carefully choreographed photocalls.
William was schooled at the elite Eton College and then spent a year off in Africa and trekking with the army in Belize.
In September 2001 he enrolled at St Andrews University in Scotland where he met his bride-to-be. They very publicly split up in 2007, but were soon reconciled.
William joined the military, following a well-trodden royal path, and he currently works as a Royal Air Force search and rescue helicopter pilot.
Last year he embarked on his first official overseas tour, to Australia and New Zealand, and received a warm welcome when he returned there this year.