Washington - By picking Senator Joe Biden, 65, as his running mate, Democratic presidential candidate Barack Obama, 47, did, above all, chose experience.

Almost no one in the United States Senate is politically as much of an "old hand" as the man from Delaware. This is particularly true with regard to foreign and security policy, which is Biden's specialty. After countless trips abroad, he is a known figure to leaders around the world.

The Pennsylvania-born trained attorney grew up in a Roman Catholic, working class home. He first joined the US Senate in 1973, to become the fifth-youngest senator in the country's history.

Biden has been for years a member of the Senate's Committee on Foreign Relations, which he currently chairs. Like Obama, he is a staunch opponent of the Iraq war, although he initially voted in favour of it in Congress in 2002.

Biden is considered a brilliant orator, full of humour. However, he is also a man whose loose tongue has at times caused him great embarrassment.

In the current campaign, he initially sought the Democratic Party's presidential nomination, although he stood no chance and gave up early on in the race.

His presidential campaign in 1988 fell through on accusations of plagiarism.

In his private life, Biden suffered tough blows from fate. His first wife and young daughter were killed in a traffic accident in late 1972. In 1988, the senator himself suffered two brain aneurysms that put his life at risk and required surgery.