Short answers, pulled from the story.
Jerónimo de Ayanz y Beaumont patented the first steam-powered water pump in 1606 to drain flooded mines. This invention marked the first instance of steam power being used to solve a real-world problem.
Thomas Newcomen invented the first commercially successful steam engine around 1712. This atmospheric engine utilized a piston within a cylinder to create a partial vacuum by condensing steam inside.
Richard Trevithick built the first full-scale working railway steam locomotive in the United Kingdom on the 21st of February 1804. This locomotive hauled 10 tonnes of iron, 70 passengers, and five wagons along the tramway from the Pen-y-darren ironworks to Abercynon in south Wales.
Steam turbines virtually replaced reciprocating engines in electricity generating stations early in the 20th century. Today, most electric power is provided by steam turbines, with 90% of the electric power in the United States produced this way.
Two German scientists at the University of Stuttgart developed the world's smallest working steam engine in 2011. This engine operates on the principle of a Stirling engine and demonstrates that the technology still holds potential for niche applications.