The original Porsche 911 (pronounced as nine eleven, German: Neunelfer) was a sports car made by Porsche AG of Stuttgart, Germany. The famous, distinctive, and durable design was introduced in autumn 1963 and built until 1989, when it was succeeded by a modified version which, despite internally called Porsche 964, was still sold as Porsche 911 (as are current models). Mechanically, the 911 was notable for being rear engined and air-cooled.
Since its inception the 911 has been modified, both by private teams and the factory itself, for racing, rallying and other types of automotive competition. It is often cited as the most successful competition car ever, especially when its variations are included, mainly the powerful 935 which won 24 Hours of Le Mans and other major sports cars races outright against prototypes. In the international poll for the award of Car of the Century, the 911 came fifth after the Ford Model T, the Mini, the Citroën DS and the Volkswagen Beetle.
It is the most successful surviving application of the air (or water) cooled opposed rear engine layout pioneered by its original ancestor, the Volkswagen Beetle.