Final answer:
Sherlock Holmes, a creation of Sir Arthur Conan Doyle, is the fictional detective who lived at 221B Baker Street in literature.
Step-by-step explanation:
The fictional detective who lived at 221B Baker Street is none other than the renowned Sherlock Holmes. Sherlock Holmes was not a real person; he was the ingenious creation of British author Sir Arthur Conan Doyle. This iconic character, known for his exceptional analytical skills and ability to solve complex cases, has left a profound impact on the genre of mystery and detective literature. The Baker Street address is now iconic, associated globally with the detective's keen intellect and the exciting mysteries he unraveled alongside his companion, Dr. John Watson.