Martin Heidegger was a German philosopher known for his influential work in existentialism and phenomenology. Born in 1889, he is best known for his book, Being and Time, where he explores the nature of existence and what it means to be. Heidegger's ideas challenge traditional philosophy by focusing on human experience and our relationship with the world around us. Heidegger's thoughts have had a significant impact on various fields, including literature, psychology, and theology. His concept of Dasein, which refers to the experience of being, emphasizes the importance of individual perspective. Despite his controversial political affiliations during the 1930s, Heidegger's work continues to inspire and provoke discussion in contemporary philosophy.