Per Martin-Löf is a Swedish logician and mathematician, best known for his work in the fields of type theory and constructive mathematics. He developed the Martin-Löf type theory, which serves as a foundation for both mathematics and computer science, particularly in the area of programming languages and proof assistants. Born in 1942, Martin-Löf has made significant contributions to the philosophy of mathematics, emphasizing the importance of constructive proofs. His work has influenced various domains, including category theory and proof theory, and he has been recognized for his efforts in bridging the gap between logic and computation.