What is the name of Sherlock Holmes's loyal friend and biographer?

Sherlock Holmes’s loyal friend and biographer is Dr. John Watson. A former army doctor, Watson meets Holmes in A Study in Scarlet and becomes his roommate, companion, and the principal narrator of many detective cases.

Watson’s role is more than that of a sidekick. He provides practical assistance, medical knowledge, courage, and an ordinary human perspective on Holmes’s extraordinary powers of deduction. Because Watson does not immediately see every connection, readers can follow the mystery alongside him before Holmes explains the solution.

Holmes repeatedly describes Watson as his faithful friend and biographer, and Watson presents the detective’s cases as written accounts. This framing device gives the stories their distinctive blend of mystery, adventure, and retrospective explanation. Holmes even compares Watson to Boswell, the famous biographer of Samuel Johnson.

A common mix-up is to choose Mycroft Holmes, Sherlock’s brilliant older brother. Mycroft can outthink Sherlock in some matters but is not his principal companion or chronicler. Inspector Lestrade is a Scotland Yard detective who sometimes helps Holmes, while Mrs. Hudson is the duo’s landlady.