Short answers, pulled from the story.
George Cayley constructed a successful passenger-carrying glider in 1853 that carried a human across a field in England. This work laid the foundation for all future aviation attempts.
The American Wright brothers flew their first airplane on the 17th of December 1903. This event is recognized by the Fédération Aéronautique Internationale as the first sustained and controlled heavier-than-air powered flight.
The Messerschmitt Me 262 became the first operational jet fighter aircraft going into service in the German Luftwaffe in 1943. Most jet aircraft use turbofan jet engines that employ a gas turbine to drive a ducted fan accelerating air around the turbine to provide thrust.
In the United States the Federal Aviation Administration authorizes mass production after an aircraft fulfills all requirements. Representatives from aviation governing agencies often make first flights before public agencies authorize mass production.
Air travel is approximately ten times safer than travel by bus or rail when measured by deaths per passenger kilometer. There is significant difference between safety of airliners and smaller private planes with per-mile statistic indicating airliners are 8.3 times safer than smaller planes.