Legendary American singer and songwriter Bob Dylan turns 70 years Tuesday, with 34 studio albums, more than 500 songs and 3000 concerts to his name.

He is arguably the greatest songwriter of all time, probably the most prolific, and is still touring after all these years. With dozens of awards, 11 Grammys, an Oscar, two doctorates - he fell asleep during the 2004 ceremony at St Andrews; the other was from Princeton in 1970 - and several nominations for the Nobel Literature Prize.

Dylan has enjoyed a career spanning 50 years in which he has written about love and death, politics and war. He has performed with guitar, keyboards, and harmonica.

Backed by a changing line-up of musicians, he has toured steadily since the late 1980s on what has been dubbed as the Never Ending Tour. His accomplishments as a recording artist and performer have been central to his career, but his greatest contribution is generally considered to be his songwriting.