>inb4 le ebic made up measure theorypseuds
>>10905119he discovered the modern framework for algebraic geometry, which is at its root the study of solution sets of simultaneous polynomials in several variables.
he is credited with developing categorical tools (ones from category theory) to analyze and generalize these solution sets, often called "varieties," into abstract objects like "schemes" and "sheaves" which combine a variety topological, algebraic, and geometric concepts. these tools are now used all over the place.
basically, he founded a massive portion of modern mathematics.
