Jakob Steiner was a Swiss mathematician born on March 18, 1796, in the city of Bern. He is best known for his contributions to geometry, particularly in the fields of projective geometry and differential geometry. Steiner's work laid the foundation for many modern geometric concepts and he introduced several important theorems and definitions. Steiner also made significant advancements in the study of conic sections and stereometry, which deals with the properties of three-dimensional figures. His influence extended beyond his lifetime, impacting future mathematicians and shaping the development of geometry as a discipline. He passed away on April 1, 1863.