the boeing 737 classic is the name of the 737-300/-400/-500. however, they were only called the 737 classics after the 737 next generation (737-600/700/800/900) aircraft were made. until then, the 737 classics were called the 'new generation' of the 737. the 737 classics were made from 1984 to 2000. 1,988 aircraft were delivered in that time. as of january 1, 2001, 1,945 are in service.