By Adam Boulton, Political Editor
Margaret Thatcher was Britain's first, and so far only, female Prime Minister. She was a transformative leader who reversed conventional wisdom that Great Britain's national decline was inevitable.
She will be remembered for curbing the trade unions, privatising state-owned industries, leading Britain to victory in the Falklands War, and as US President Ronald Reagan's staunch ally in confronting the Soviet Empire.
Mrs Thatcher is now ranked alongside Sir Winston Churchill (her hero) and Clement Attlee as one of Britain's most important 20th century prime ministers, but the "Iron Lady", as she was nicknamed, was a deeply divisive figure, openly hated by many, especially those from industrial heartlands, which she sent to the wall.
She ended her 11-year premiership quite literally in tears, thrown out not by the voters but by the very Conservative MPs she had led to three successive general election victories.
Margaret Hilda Roberts was born on October 13, 1925, the daughter of a grocer and alderman from Grantham in Lincolnshire. She idolised her father but seldom even mentioned her mother.
A clever and ambitious grammar school girl, she won a place at Oxford University to study chemistry, going on to work in industry as a research chemist - working in the team that invented Mr Whippy ice cream.
She had determined political ambitions as well, fighting Dartford for the Conservatives unsuccessfully in the 1950 and 1951 general elections.
Her consolation was to meet and marry Denis Thatcher, a prosperous businessman and Tory activist.
With typical efficiency, Mrs Thatcher gave birth to twins, a boy and a girl, Mark and Carol. She did not enter parliament until 1959 as the member for Finchley, a North London constituency she held for 23 years until her retirement.
In 1967 Tory leader Edward Heath invited her to join his shadow cabinet and made her education secretary following his unexpected triumph over Harold Wilson in the 1970 general election.
The rising star told a television interviewer that she did not expect to see a woman prime minister in her lifetime but she attracted less favourable publicity when she cancelled free school milk, becoming known as Margaret Thatcher, Milk Snatcher.
Ted Heath lost the two elections in 1974 and was forced out as leader after a protracted period of party infighting.
She became Conservative Party leader in 1975 and won the election in 1979
Margaret Thatcher only stood against him after her mentor Sir Keith Joseph declined to run. An outsider in many ways, she was nonetheless elected Conservative Party Leader in 1975.
Prime Minister Callaghan took over from Wilson, but Labour's left-right tensions spilt over into protracted industrial unrest.
Mrs Thatcher stormed into Downing Street on May 4, 1979, following a Conservative election campaign which focused on the economic paralysis of the nation during the so-called Winter of Discontent.
On the steps of Number 10 she quoted St Francis and promised to bring unity. But the British economy plunged still further, unemployment trebled to more than three million. London and Liverpool suffered inner city riots.
After two years in office, Margaret Thatcher was one of the most unpopular Prime Ministers ever. She was rescued by Argentina's military junta in 1982.
Against the advice of her ministers and most military commanders she ordered a task force 3,000 miles into the South Atlantic to recapture the Falkland Islands from Argentine invaders.
The Conservatives returned to power in the 1983 general election with an increased majority.
Mrs Thatcher moved on to confront what she called the "enemy within", eventually defeating a bitter and confrontational year-long miners' strike over pit closures, unwisely called by NUM leader Arthur Scargill without a ballot of his members.
Irish Republican terrorists murdered two of Mrs Thatcher's closest political colleagues Airey Neave and Ian Gow. And in October 1984 five friends and colleagues were killed when the IRA blew up the Grand Hotel in Brighton during the Conservative Party Conference.
Mrs Thatcher with US President Ronald Reagan at the White House in 1987
Margaret, the wife of her close political ally Norman Tebbit, was among those victims crippled for life.
Yet a year later Mrs Thatcher and her counterpart Garret Fitzgerald signed the Anglo-Irish Agreement, which would ultimately provide the diplomatic basis for the end of The Troubles.
Mrs Thatcher also became a prominent and pugnacious figure on the world stage. She secured the rebate on Britain's contribution to the European Community and pressed for an open market.
Her decision to deploy tactical nuclear weapons in Britain led to the Greenham Common protest but it was also part of the arms build-up which ultimately broke the Soviet Union and brought down the Iron Curtain.
Mrs Thatcher was quick to spot the new Soviet leader Mikhail Gorbachev as "a man I can do business with". But for his two terms as American President Ronald Reagan was Mrs Thatcher's closest ally - on foreign affairs and on economic and social policy.
Her economic ideology was unswerving. She believed in a smaller state, lower taxes, self-reliance and people being left to spend "their own money".
Her government sold or "privatised" state-owned "nationalised" assets - first council houses then shares in gas, electricity, water and telecommunications and "the big bang" de-regulating banking and the City of London.
She set BT on the road to privatisation
She won a third election in 1987 with another huge majority but like many long-serving successful leaders, she began to believe her own publicity, epitomised in her most famous quotation: "The Lady is not for turning".
Domineering and unwilling to listen, she alienated many of her ministers and MPs.
By now Michael Heseltine had resigned from government and established himself as a leader-in-waiting. He exploited growing discontent over two issues: the proposed Community Charge or Poll Tax, and hostility to Europe.
Anti-poll tax demonstrations brought some of the worst street violence in living memory.
Her stubborn opposition to further European integration provoked first the resignation of her chancellor Nigel Lawson, then, fatally, of her deputy prime minister Sir Geoffrey Howe.
She stood down in November 1990, after failing to secure the overwhelming support of MPs in yet another Heseltine-inspired leadership contest on the very night European leaders were celebrating the fall of the Berlin Wall.
One of Prime Minister Thatcher's last achievements was persuading the new US President George Bush senior not to "go wobbly" following Saddam Hussein's invasion of Kuwait.
Mr Heseltine failed to seize the crown and instead the Conservative party united around John Major, Thatcher's relatively obscure preferred successor.
Leaving Downing Street for the last time in 1990
In 1992, Mr Major led the Tories to victory over Neil Kinnock's Labour yet again.
In her retirement, the Queen made Mrs Thatcher a member of the Order of the Garter and appointed her Baroness in the House of Lords. Her husband Denis received a hereditary knighthood.
Sir John Major sometimes complained of "back seat driving" as the former PM relished the movie title "The Mummy Returns".
The next Labour Prime Minister Tony Blair never bothered to hide his admiration for her decisive style of leadership but there was widespread astonishment when the newly-elected Labour Prime Minister Gordon Brown invited her back to Downing Street for tea in her honour.
More recently, Meryl Streep won an Oscar for a portrayal of Margaret Thatcher in the Hollywood movie 'The Iron Lady'. But the film also depicted unflinchingly the politician's descent into senile dementia, hastened by the death of her beloved husband, Denis.
A car travels through the snow near Allenheads in Northumberland 
Geoff Lee at an ice wall which has formed on Durham Dales 
Magaret Thatcher was a very divisive figure 
Some people celebrated news of Thatcher's death 
Five died in the fire on October 19, 2012 
Firefighters were unable to save the family 
Wigan Athletic owner Dave Whelan also wanted a minute's silence 
Margaret Aspinall (R) lost her son in the Hillsborough disaster 
The scene where Mrs Castle was mugged 
Lead scientists Stefan A. F. Bon (Credit: University of Warwick) 
Scientists used apple, orange and cranberry juice 
Iain Duncan Smith: Old system is "ridiculous" 
Campaigners handing in the IDS petition at Caxton House, central London 
