Everything you need to know about Prince Phillip as he announces he'll step down from official duties
He is the Queen's husband and the Royal Family's patriarch, but what is the Duke of Edinburgh known for?
1. Devotion to the Queen
The Duke has spent nearly 70 years as the Queen's companion. His support has been unwavering as he has stood by her side through each decade of her reign. He is the longest serving consort in British history - supporting the nation's longest reigning monarch.
Their compatibility has led to a successful long marriage - despite their contrasting personalities - with Philip seen as adventurous and tempestuous, and the Queen as more passive, cautious and conventional.
Always one step behind Elizabeth II, the Duke has always let the monarch take centre stage, but has accompanied her throughout the triumphs and trials of her role as head of state.
2. Public duty
Philip's life has been devoted to public duty. He has carried out thousands of engagements in the UK and around the world - from entertaining visiting presidents and hosting charity receptions to holding private dinners for military organisations.
3. His gaffes
Philip's controversial comments - from describing Chinese people as "slitty eyed" to asking a sea cadet whether she worked in a strip club - are legendary.
The Duke has never curbed his off the cuff remarks, and even at the age of 94 he was caught on camera swearing at an RAF photographer for taking too long to take a picture.
Despite the criticism he has faced, Philip is famed for spicing up even the dullest of royal engagements.
4. The Duke of Edinburgh Award
He set up his youth achievement award in 1956 and it has become one of the best known self development and adventure schemes for 14-24 year-olds.
Millions have signed up to work towards their Bronze, Silver and Gold awards and the scheme has been praised for challenging young people and broadening their horizons.
5. No fuss approach
The Duke is a no nonsense man, who cannot bear a fuss. He is not interested in his own legacy, illness does not require sympathy and his birthdays are kept as low key as possible.
6. Royal patriarch
Although the Queen is head of state, it is Philip who is head of the Royal Family.
A firm father, the Duke takes the lead behind closed doors. He also takes charge of family barbecues when the royals holiday at Balmoral.
7. Carriage driving
Philip is synonymous with carriage driving. He loves nothing more than to go haring through the countryside at high speed, whip in hand, in a horse drawn, wheeled carriage.
"I am getting old, my reactions are getting slower, and my memory is unreliable, but I have never lost the sheer pleasure of driving a team through the British countryside," he explained in the book he wrote about the sport.
The Duke is also a keen oil painter.
8. Naval service
He could have been First Sea Lord - the professional head of the Navy - had he not married Princess Elizabeth. But his naval career came to an end in 1951 due to the failing health of his father in law George VI, and when his wife became Queen a year later his destiny was set.
His life at sea - following distinguished service during the Second World War - was put aside for royal duty, but he has always maintained close connections to the armed forces and their organisations.
For Philip's 90th birthday, the Queen - who is well aware what he sacrificed - poignantly bestowed upon him the title of Lord High Admiral, titular head of the Royal Navy.
9. Dashing prince
Philip was Princess Elizabeth's Prince Charming. Tall, blond and athletic, he was a royal heartthrob in the 1940s when he romanced the future Queen and married her in a fairytale ceremony.
10. Charity work
The Duke is patron of countless organisations and charities. When he turned 90, he stepped down as president or patron of more than a dozen organisations - but has still been involved with some 800 charities or bodies.
He has always been particularly interested in scientific and technological research, industry, the conservation of the environment and the encouragement of sport.
11. A moderniser
When the Queen first became monarch, she gave Philip the task of reorganising her Balmoral and Sandringham estates, which he did with ruthless efficiency.
He set about modernising Buckingham Palace after being told by aides to keep out of the Queen's official duties.
He is also Ranger of Windsor Great Park and has been fundamental to the upkeep of vast parkland, from designing gardens to introducing deer.
12. Not being Prince Consort
Queen Victoria's Prince Albert was Prince Consort, but Philip, despite his longevity as a royal consort, has never been given the title.
Politicians suggested he be offered it, but the Duke - unconcerned with his own standing - is simply not interested.