Hasib Mir Hussain, 18
Hasib Hussain had lived all his life in the Holbeck area of Leeds. He was known as a tearaway in his youth but left school in 2003 with seven GCSEs.
Around this time, he was sent to Pakistan to visit relatives. He also went on the Hajj pilgrimage to Mecca, grew a beard and began to wear robes.
His family said they were "devastated" to learn he was the bus bomber who claimed 13 lives on 7 July.
Shehzhad Tanweer, 22
Shehzad Tanweer was born in Bradford but lived most of his life in the Beeston area of Leeds. He was a former sports science student whose interests included cricket and ju-jitsu.
Friends said he was quiet and very religious but did not express an interest in politics. He is reported to have been at an Islamic study camp in Pakistan earlier this year.
Tanweer detonated his bomb on the Circle line, killing seven.
Mohammad Sidique Khan, 30
Teaching assistant Mohammad Sidique Khan had lived in the Beeston area of Leeds until recently, when he moved to Dewsbury.
He is believed to have been married with a very young daughter. The 30-year-old had worked at Hillside Primary School in Leeds since 2002 where he appeared well-liked by staff and parents.
Despite the tributes, Mohammad Sidique Khan detonated enough explosives on a Circle Line train to kill seven people.
Germaine Lindsay, 19
Police sources have named the fourth suicide bomber as Jamaican-born British resident Germaine Lindsay, who had converted to Islam.
He had spent his childhood in Huddersfield, West Yorkshire, not far from the other bombers' homes.
He is said to be married with a 15-month-old child and another on the way.
Lindsay carried out the most deadly of the bombings, killing 27 on the Piccadilly line train.
Full profile of the four bombers
TIMELINE OF KEY EVENTS
Early on 7 July 2005, Hasib Hussain, Shehzad Tanweer and Mohammad Sidique Khan travel from their West Yorkshire homes to Luton by hire car.
At Luton station they meet Germaine Lindsay from Aylesbury, Buckinghamshire. The four are caught on CCTV as they enter the station.
The four bombers board a train for London King's Cross. Each carries a rucksack packed with explosives.
At King's Cross they fan out - Tanweer and Khan take the Circle line in opposite directions while Lindsay takes the Piccadilly line south.
Their bombs explode at 0850.
Nothing is known of Hussain's movements until 0947 when he blows up a bus in Tavistock Square.
Hasib Hussain was from Holbeck, Leeds
Friends said Shehzad Tanweer was very religious
Mohammad Sidique Khan was a respected teaching assistant
Germaine Lindsay was a convert to Islam