Margaret Thatcher was Britain's longest serving prime minister of the 20th century. She dominated politics in her own country for a decade and carved out for herself a formidable position on the world stage.

Margaret Thatcher - Britain's first and only female Prime Minister.

She governed from 1979 to 1990 and was famous for her tough attitude.

Thatcher said, "I have only one thing to say: you turn if you want to. The lady's not for turning."

The grocer's daughter led the Conservative party to three election victories.

Margaret Thatcher [File photo]

David Cameron, British Prime Minister, said, "The real thing about Margaret Thatcher, is that she didn't just lead our country, she saved our country."

Known as the Iron Lady, she was loved and hated in equal measure and remains a divisive figure to this day.

Ed Milliband, Labour Party leader, said, "We disagreed with much of what she did as a Labour party, but we can disagree but also respect her extraordinary achievements."

While in 10 Downing Street she introduced social and economic reforms designed to end what she saw as a spiral of industrial decline, crippling taxes and state control.

She privatised numerous state monopolies - like gas, oil, steel, telephones and airports - while deregulating the economy.

David Tinsley is Chief UK Economist at BNP Paribas.

David Tinsley said, "That emphasis on liberalisation of economies and free markets also meant that that emphasis was really put within the financial sector as well and you could say that the build up to some financial excesses in the 2000s and the subsequent crash found their seeds in the 80s and 90s."

In 1985 she stopped a year-long strike by English miners. After that, unions were no longer able to dictate to British governments.

Thatcherism made many better off but by the mid 1980s her economic medicine saw unemployment hit a level not seen since the 1930s, and left industries destroyed.

The highly unpopular poll tax led to riots, and ultimately her downfall.

Her right-wing views broke the mould of British politics and have had lasting repercussions.

Her reluctance about greater European integration defines Britain's relationship with the EU to this day, says Commission President Jose Manuel Barroso.

Jose Manuel Barroso said, "She will be remembered both for her contributions and her reserves to our common project. She signed the Single European Act and she helped bring about the single market. She was a leading player in bringing into the European family the central and eastern European countries."

Years later Thatcher was blamed for worsening the divide between rich and poor.

But she undoubtedly shaped Britain's economy - which without her would have been more centralised and less flexible.