Viktor E. Frankl was an Austrian neurologist, psychiatrist, and Holocaust survivor. He is best known for his book Man's Search for Meaning, which chronicles his experiences in Nazi concentration camps and his psychological theories on finding meaning in life. Frankl developed a form of psychotherapy known as logotherapy, which focuses on finding meaning in life through suffering and creating a sense of purpose. He believed that the primary motivation in life is the search for meaning, and that this search is the key to mental health and well-being. Frankl's work has been influential in the fields of psychology, psychiatry, and philosophy, and has been credited with helping to shape the modern understanding of mental health and resilience. He is remembered as a pioneer in the field of existential psychology, and his legacy continues to inspire people around the world.