Short answers, pulled from the story.
Henry Cavendish discovered hydrogen in 1766 and called it inflammable air. He was the first to recognize it as a distinct substance and demonstrated that burning it produced water. Antoine Lavoisier later named the element hydrogen in 1783 after reproducing Cavendish's experiment.
The hydrogen atom consists of a single proton and a single electron in its most common form known as protium. Protium contains no neutrons to slow down the particle. This simple structure makes it the lightest element in the universe.
Harold Urey discovered deuterium in December 1931. This isotope contains one neutron and forms heavy water which serves as a neutron moderator in nuclear reactors. Deuterium is also used in nuclear fusion research today.
The Hindenburg airship caught fire over New Jersey possibly ignited by static electricity. The hydrogen gas inside the vessel burst into flames and ended commercial hydrogen airship travel. This tragedy occurred in 1937 after regular passenger service had begun in 1910.
Nearly all hydrogen produced today comes from fossil fuels through steam methane reforming. This process emits carbon dioxide and contributes to the global carbon footprint. The industrial demand for hydrogen is driven by the Haber process which uses it to produce ammonia for fertilizers.