William and Kate arrived in Ottawa, Canada on Thursday for their first official foreign visit as a married couple.

Just like Michelle Obama, what Kate will wear attracts a lot of attention. She even has her own website that chronicles all her clothes called What Kate Wore. If you know Duchess had changed her clothes on Thursday, you can understand how the website is indispensable.

Even when Kate was William's girlfriend at St. Andrews University, what she wore already became the hot topic. Now Kate's fashion influence the whole world. In another word, Kate Middleton's evolution creates fashion revolution.

Kate Middleton is seen attending the Cheltenham Festival in Gloucestershire, western England in this March 16, 2007 file photograph.

Kate Middleton studies a race card on the final day of the Cheltenham Festival horse racing in Gloucestershire, western England, March 16 2007.

Kate Middleton watches the first race at the Cheltenham Festival horse racing meeting in Gloucestershire, western England March 14, 2008.

Britain's Prince William (L) smiles as he walks with Kate Middleton at RAF Cranwell, central England April 11, 2008. William, watched by his admiring Middleton, received his Royal Air Force wings from Prince Charles on Friday. William, the fourth successive generation of the monarchy to become an RAF pilot, learned to fly on his four-month attachment.

Kate Middleton enters a room with Britain's Prince William, to pose for a photograph in St. James's Palace, central London November 16, 2010.

Kate Middleton smiles as she arrives to attend a Naming Ceremony and Service of Dedication for the Royal National Lifeboat Institution's (RNLI) new Atlantic 85 Lifeboat, the 'Hereford Endeavour', at Trearddur Bay Lifeboat Station, in Trearddur Bay, Anglesey in north Wales February 24, 2011.

Kate Middleton smiles during her visit to St. Andrews University in Fife, Scotland February 25, 2011. Kate and Prince William made their second official visit together since announcing their engagement in November to St. Andrews University to launch its 600th anniversary celebrations.

Kate Middleton speaks with well-wishers during their visit to Witton Country Park in Darwen, northern England April 11, 2011. A large crowd of well-wishers braved a downpour in northern England on Monday to cheer Prince William and Kate Middleton.

Kate Middleton arrives at The Goring hotel in London April 28, 2011, the day before her wedding on April 29.

Kate Middleton arrives to Westminster Abbey for her marriage to Britain's Prince William in central London April 29, 2011.

Kate Middleton, Duchess of Cambridge, leaves Clarence House to travel to Buckingham Palace for the evening celebrations following her wedding to Prince William in London April 29, 2011.

Britain's Prince William and Kate, Duchess of Cambridge, walk together hand-in-hand in Buckingham Palace, following their wedding on Friday, in central London April 30, 2011.

Kate Middleton, Duchess of Cambridge, smiles as she arrives at the 10th annual Absolute Return for Kids (ARK) gala dinner at Kensington Palace in London June 9, 2011.

Kate Middleton, Duchess of Cambridge, smiles as she rides to Buckingham Palace after attending the Trooping the Colour ceremony in central London June 11, 2011. Trooping the Colour is a ceremony to honor the sovereign's official birthday.

Kate Middleton, Duchess of Cambridge, leaves St. George's Chapel, with other members of the royal family, after a service to mark Prince Philip's 90th birthday, in Windsor, west of London June 12, 2011.

Kate Middleton, Duchess of Cambridge, watches the procession pass at the Order of The Garter Service in Windsor, England June 13, 2011.

Kate Middleton, Duchess of Cambridge, arrives on Centre Court for the match between Andy Murray of Britain and Richard Gasquet of France at the Wimbledon tennis championships in London June 27, 2011.

Kate Middleton, Duchess of Cambridge is seen wearing a smart blue coat as she visits Victoria Barracks for a medal presentation ceremony to the 1st Battalion Irish Guards, on Armed Forces Day in Windsor, southern England June 25, 2011.

Kate Middleton, Duchess of Cambridge reveals grace and elegance as she arrives at Macdonald-Cartier International Airport June 30, 2011 in Ottawa. The Royal couple arrived in Canada on Thursday for their first official visit overseas as a married couple.

Kate Middleton, Duchess of Cambridge, takes part in Canada Day celebrations on Parliament Hill in Ottawa July 1, 2011. Prince William and his wife Catherine, Duchess of Cambridge, are on a royal tour of Canada from June 30 to July 8.