Introduced into a busy market for short-haul jet arilines in the mid 1960s, Boeing's 737 has gone on to become one of the world's most successful and numerous airliners. There can be few regular flyers who have not travelled on a 737, and the number of airlines that do not have one on their registers is small. The aircraft's progress through turbulent political and commercial times is followed, as is the 737's own operational history and its own undoubted influence in the constantly changing airliner industry of the last quarter of the 20th century and beyond.