Sir Arthur Doyle was a Scottish physician and writer who is most noted for his fictional stories about the detective Sherlock Holmes, which are generally considered milestones in the field of crime fiction. He is also known for writing the fictional adventures of a second character he invented, Professor Challenger, and for popularising the mystery of the Mary Celeste. He was a prolific writer whose other works include fantasy and science fiction stories, plays, romances, poetry, non-fiction, and historical novels. Sherlock Holmes is a fictional detective created by Scottish author and physician Sir Arthur Conan Doyle, a graduate of the University of Edinburgh Medical School. A London-based "consulting detective" whose abilities border on the fantastic, Holmes is famous for his astute logical reasoning, his ability to adopt almost any disguise, and his use of forensic science skills to solve difficult cases.