Today marks the 125th birth anniversary of one of India's best known mathematicians, Srinivasa Ramanujan. Google has marked the event in its customary fashion with a doodle.

A gifted mathematician, Ramanujan was born in Erode, Tamil Nadu.

Ramanujan was born in a poor family but his natural mathematical abilities ensured that he would one day become a Fellow of the Royal Society.

Prime Minister Manmohan Singh has announced 2012 to be the National Mathematical Year to celebrate Ramanujan's birthday.