Probability theory has evolved through the contributions of many mathematicians and scientists. Early work by Blaise Pascal and Pierre de Fermat in the 17th century laid the groundwork for understanding random events and gambling. Their correspondence introduced concepts like expected value and combinatorial analysis, which are fundamental to the field. In the 20th century, Andrey Kolmogorov formalized probability theory by establishing axioms that define probability spaces. His work provided a rigorous mathematical framework, allowing for the application of probability in various fields, including statistics, finance, and science. This formalization has made probability a crucial tool for decision-making under uncertainty.