A sports car has been defined as "an open, low-built, fast motor car." Sports cars have been either spartan or luxurious, but driving and mechanical performance is requisite. A sports car does not require a large, powerful engine, though many do have them. Many classic British sports cars lacked powerful engines, but were known for exceptional handling due to light weight; a well-engineered, balanced chassis; and modern suspension (for example, Lotus Seven, Austin 7 Speedy).