Short answers, pulled from the story.
Joe Sutter led the design of the Boeing 747 after being transferred from Boeing's 737 development team in 1965. Pan Am placed the formal launch order for 25 aircraft in April 1966, and Boeing's board approved production in July 1966 once Japan Airlines and Lufthansa also placed orders.
The Boeing 747 entered commercial service on the 22nd of January 1970 on Pan Am's New York-London route. The inaugural flight was delayed more than six hours because the original aircraft, Clipper Young America, developed engine overheating on the tarmac, and a substitute, Clipper Victor, had to be found.
A total of 1,574 Boeing 747s were built over a 54-year production run. The final aircraft, a 747-8F registered N863GT, was delivered to Atlas Air on the 31st of January 2023.
In its standard three-class configuration the 747 typically accommodates 366 passengers, with a 3-4-3 seat arrangement in economy class. The 747-300 increased capacity to up to 400 seats in three classes, while the Japanese short-range 747SR variant was configured to carry up to 550 passengers.
The 747's hump exists because the cockpit was placed on a raised, shortened upper deck so that a front-loading cargo door could be installed in the nose cone on freighter variants. Early designs considered a full double-deck fuselage, but evacuation concerns led engineers to adopt the distinctive raised-cockpit solution instead.
The 747-400, introduced in 1989, is the most common variant. It features a two-crew glass cockpit that eliminated the flight engineer's position, new engines, and lighter construction materials. Boeing cut the cockpit instrument count from nearly 690 dials and lights to 300 indicators.