The Olympic torch is a symbol of the Olympic Games and is traditionally lit in Olympia, Greece - the birth place of the Games - before being taken to the host city.
Initial editions of the modern Olympic Games were held without the flame, and it was only 1928 that it was re-introduced.
The torch's origin lies in ancient Greece where a flame burned on the altar of Goddess Hera throughout the Games. And the torch relay is inspired by the tradition of heralds travelling across the Greece to announce the Games.
Keeping up with the tradition, the Olympic torch is lit from the Sun rays at the temple of Goddess Hera. It travels across the Greece before being handed over to the host city at the Panathenaiko stadium.
Once the torch arrives in the host city, a number of torchbearers carry the flame and spread the message of unity, peace and friendship. The last torchbearer lights the cauldron at the Olympic stadium. The flame is extinguished on the last day of the Games.
Here are some facts about the London Olympics torch:
The Olympic Torch features 8,000 small cut-out circles, representing the 8,000 people who carried it on its journey around the UK.
The small circles which run the length of the body of the Torch make it unique in the way that a person can see right through and view the burner system which will keep the Olympic Flame alive on its journey around the UK.
In April 2012, the Torch was recognised as the Design of the Year at an awards ceremony hosted by the Design Museum. The Torch's triangular shape symbolises a series of 'threes': Olympic values of respect, excellence and friendship; the three words that make the Olympic motto - faster, higher, stronger; the UK hosting the Olympic Games for the third time - They have previously hosted Olympics in 1908, 1948; and the vision for the London Games to combine three bodies of work - sport, education and culture.
The Torch has been made as light as possible since more than half of the torchbearers were young people, aged as young as 12. The Torch weighs 1kg, including the burner and gas canister, and stands 800 mm high.
The body of the gold-coloured Torch is made up of an aluminum alloy that is held in place by a cast top piece and base.
Olympics 2012 - Medals Tally