Baudhayana, (\(800\) BCE) was an ancient Indian mathematician. He is noted as the author of Sulba Sutra (vedic rules for construction of altars - called the Baudhayana sulbasutra). This book contains several important mathematical results.
Baudhayan used a rope as an example in his shloka which can be translated as - 'A rope stretched along the length of the diagonal produces an area which the vertical and horizontal sides make together'.
The mathematical form of this will look like as follows:

'The diagonal of a rectangle produces by itself the same area as produced by its length and breadth'.
Baudhayan discussed several concepts in Mathematics, which were later rediscovered by the western world. The Pythagoras theorem that we learned is already found in Baudhayan's Sulba Sutra, which was written several years before the age of Pythagoras.
Applying the Baudhayan theorem, we have:
\(a² + b² = c²\).
The value of 'pi - π' was first calculated by Baudhayan. 'π' is useful in calculating the area and circumference of a circle.