William Thurston was an influential American mathematician known for his work in the field of topology, particularly in the study of three-dimensional manifolds. He introduced the concept of hyperbolic geometry and developed the Thurston norm, which helps classify the types of surfaces in three-dimensional spaces. His contributions significantly advanced the understanding of the structure of 3-manifolds. In 1982, Thurston was awarded the prestigious Fields Medal for his groundbreaking research. He also authored the influential book "The Geometry and Topology of 3-Manifolds," which has become a key resource for mathematicians studying topology. His work continues to inspire new generations of mathematicians.