Abulcasis Al-Zahrawi is an Arab Muslim physician who lived in Andalusia. He is considered the greatest surgeon who appeared in the Islamic world, and many described him as the father of modern surgery. His greatest contribution to medicine is the book Al-Tasrif for the Unable to Write, which is a thirty-volume medical encyclopedia. His medical contributions, whether in the medical techniques used or the devices he made, had a great impact in the East and West, so that some of his inventions are still used today. Al-Zahrawi is the first doctor to describe an ectopic pregnancy, and he was the first to discover the genetic nature of hemophilia.