Rolls-Royce Limited was a British luxury car and later an aero-engine manufacturing business established in 1904 in Manchester by the partnership of Charles Rolls and Henry Royce. Building on Royce's good reputation established with his cranes, they quickly developed a reputation for superior engineering by manufacturing the "best car in the world". The business was incorporated as "Rolls-Royce Limited" in 1906, and a new factory in Derby was opened in 1908. The First World War brought the company into manufacturing aero-engines. Joint development of jet engines began in 1940, and they entered production in 1944. Rolls-Royce has since built an enduring reputation for the development and manufacturing of engines for military and commercial aircraft.