Short answers, pulled from the story.
George Stephenson was an English civil and mechanical engineer who lived from 1781 to 1848 and pioneered steam rail transport. He built the Stockton and Darlington Railway and the Liverpool and Manchester Railway, and his chosen 4 ft gauge became the standard gauge used by most of the world's railways.
The Stockton and Darlington Railway opened on the 27th of September 1825. Driven by Stephenson, the locomotive Locomotion hauled an 80-ton load of coal and flour nine miles in two hours, the first time passenger traffic had run on a steam locomotive railway.
The Geordie Lamp was a miners' safety lamp George Stephenson devised in 1815, in which air entered through tiny holes too small for the flames to pass back through. It used a perforated plate around a glass cylinder, while Humphry Davy's rival lamp surrounded the flame with a screen of gauze.
George Stephenson's entry in the Rainhill Trials of October 1829 was Rocket, which won the contest and became famous. His son Robert handled Rocket's detailed design, and it used a fire-tube boiler invented by French engineer Marc Seguin and suggested by Henry Booth.
George Stephenson died of pleurisy at noon on the 12th of August 1848, aged 67, at Tapton House in Chesterfield, Derbyshire. He was buried at Holy Trinity Church in Chesterfield, alongside his second wife.
George Stephenson chose a 4 ft gauge for the Stockton and Darlington Railway, and it was later adopted as the standard gauge for railways across Britain and the world. He foresaw that individual lines would eventually be joined and would need the same gauge.