Srinivasa Ramanujan was, without doubt, a mathematical genius. Without any formal training in the subject, he made significant contributions to the theory of numbers, investigation of elliptical functions, infinite series, continued fractions, and Mock theta functions.
Ramanujan showed a natural inclination towards mathematics when he was ten years old. By age 11 he had more mathematical knowledge than two college students who were lodgers at his home. He completely mastered advanced trigonometry by the age of 13, and discovered sophisticated theorems on his own.
His memory for mathematical formulae and constants seems to have been boundless- he amazed classmates with his ability to recite the values of irrational numbers to as many decimal places as they asked for.
Ramanujan went to Cambridge in April 1914, thanks to the help of Prof. G. H. Hardy. Two years later, he was awarded the equivalent of a PhD. for his work. The notebooks he had brought from India were filled with thousands of identities, equations and theorems which he had discovered for himself.
In 1918 Ramanujan became the first Indian Mathematician to be elected a Fellow of the British Royal Society.