You've come a long way, baby!
I've always been an aviation enthusiast, sopping up all I could about the subject, from the first manned ascent by the Montgolfier brothers in a hot air balloon in 1783 to the almost-science-fiction-like aircraft of today.
Until the late 1960's-early 1970's American commercial airplane makers Boeing, Lockheed, and Douglas were the big players, with the Europeans lagging far behind. That's when the French, Germans, Brits (and later the Spanish) joined together in a consortium to form what we know today as Airbus.
I like Airbus, mainly because I think it pushed the Americans into being more competitive and innovative, benefiting us all. What I didn't know until recently was that it was the most American of airlines, American Airlines, that goaded Airbus into business.
Until then long-distance aircraft that flew over tall mountains or open stretches of ocean were 3 or 4 engined per FAA regulation (although it wasn't called the FAA back then).
That's because back in the days of piston engined aircraft it wasn't uncommon for one or even two engines to be shut down in flight due to malfunction. Hence most long range aircraft aircraft of the day....DC-6 & 7, Lockheed Constellation, etc....had 4 engines for safety. (Smaller twin-engine aircraft like the DC-3 had to hug coastlines or fly thru mountain valleys.)
Engines are expensive, both to buy and service. After jet engines came into common use on the Boeing 707 and Douglas DC-8 it became obvious that jets were much more reliable, and therefore aircraft could safely fly with only 3 engines. This was the heyday of the tri-motored Boeing 727 and later the wide-bodied Lockheed L1011, and Douglas DC-10. (The mammoth 747 still retained 4 engines.)
Across the pond the Europeans knew they would have to pool their resources and talent to produce a world class aircraft alternative to the Americans or give up entirely and cede it all to the Yanks. (Their existing programs, even the vaunted Concord, were not economically successful.) That would mean the loss of lots of jobs, and their technical aerospace talent would just waste away forever.
Always looking for ways to be more efficient, it was a VP at American Airlines who began pushing for a twin-engined airliner. Remember, fewer engines = lower costs. The big American plane builders said no thanks, they were committed to their tri-motors.
This was their big chance. The Europeans took up American Airlines challenge and began work on the first wide-body, long-range, twin-engine jet, the Airbus A300. It was quite a gamble. We can see now it was a rather crude aircraft, but it was a start.
Airbus' next game changer was the A300B, which pushed the Flight Engineer out of the cockpit due to increased automation and efficiency. Now with only a pilot and co-pilot on the flight deck, payroll was reduced considerably. One less engine and one less crew member meant more $$$$ for the airline.
The rest is history. American Airlines and Airbus were right about having just two engines, and now most of the biggest, longest range aircraft (Boeing 767, 777, 787, Airbus A330, A350) and shorter range aircraft (Boeing 737 and Airbus A320 families) are twins.
I love how one guy pushing for something different stood the status quo on its head. :)
To quote the great Paul Harvey, "Now you know the rest of the story."