Stephen Hawking was an English theoretical physicist, cosmologist, and author who is best known for his work on black holes and the origins of the universe. He was a professor at the University of Cambridge and authored several popular science books, including "A Brief History of Time" which sold millions of copies worldwide. Despite being diagnosed with a motor neuron disease at a young age, he made groundbreaking contributions to the fields of theoretical physics and cosmology, such as the prediction of Hawking radiation. He was widely regarded as one of the most brilliant and influential scientists of his time, and his work continues to inspire and influence scientific research today.