He created the character Sherlock Holmes in 1887 for A Study in Scarlet, the first of four novels and fifty-six short stories about Holmes and Dr. Watson. The Sherlock Holmes stories are milestones in the field of crime fiction.

Doyle was a prolific writer; other than Holmes stories, his works include fantasy and science fiction stories about Professor Challenger and humorous stories about the Napoleonic soldier Brigadier Gerard, as well as plays, romances, poetry, non-fiction, and historical novels. One of Doyle's early short stories, "J. Habakuk Jephson's Statement" (1884), helped to popularise the mystery of the Mary Celeste.

Supported by wealthy uncles, Doyle was sent to England, to the Jesuit preparatory school Hodder Place, Stonyhurst in Lancashire at the age of nine (1868–70). He then went on to Stonyhurst College, which he attended until 1875. While Doyle was not unhappy at Stonyhurst, he said he did not have any fond memories of it because the school was run on medieval principles: the only subjects covered were rudiments, rhetoric, Euclidean geometry, algebra and the classics. Doyle commented later in his life that this academic system could only be excused "on the plea that any exercise, however stupid in itself, forms a sort of mental dumbbell by which one can improve one's mind."^[13] He also found the school harsh, noting that, instead of compassion and warmth, it favoured the threat of corporal punishment and ritual humiliation.