The Madhava-Leibniz series is a mathematical series that provides a way to calculate the value of π (pi). It is expressed as the infinite sum: π/4 = 1 - 1/3 + 1/5 - 1/7 + 1/9 - ..., where the terms alternate between positive and negative fractions. This series was independently discovered by Madhava of Sangamagrama in the 14th century and later by Gottfried Wilhelm Leibniz in the 17th century. This series converges to π/4, meaning that as more terms are added, the sum approaches the value of π/4 more closely. Although it converges slowly, it is significant in the history of mathematics for its role in the development of calculus and series expansions. The Madhava-Leibniz series is a foundational concept in understanding infinite series and their applications in various fields.