The 911 or nine-eleven is the most famous and distinctive automobile from Porsche. Released in 1963 (as the Porsche 901, before Peugeot's complaints led to a name change), the car has a 6-cylinder air-cooled engine in 'boxer' configuration at the rear. The body styling was by Butzi Porsche, son of the company founder Ferry Porsche. Erwin Komenda, the leader of the Porsche car body construction department, was involved in the design. Many racing versions of the 911 were developed and the cars won numerous prestigious circuit races and rallies.

The car underwent continuous development (including turbo-charging and four-wheel-drive), until 1997 when—still a fast car in any terms—it was replaced by an all-new 911 model. The new 911 is visually very reminiscent of the original, and retains the rear-mounted 'boxer' flat-6 engine, although it is now water-cooled to meet more stringent noise regulations. Its lines are a little sleeker and it has a much more steeply raked windshield than the original.

A notable variant of the 911 was the Porsche 959 - a turbocharged, four-wheel-drive supercar of the 1980s.