Short answers, pulled from the story.
Theodore Maiman built the first functional laser on the 16th of May 1960. He used a synthetic ruby crystal pumped by a high-intensity flash lamp to produce a pulse of red light at 694 nanometers.
Gordon Gould coined the acronym LASER and sketched the design of an optical resonator on the 11th of November 1957. He envisioned future names for different parts of the spectrum such as XASER for X-rays and RASER for radio waves.
A laser produces a beam that is spatially and temporally coherent with a very narrow frequency spectrum. Thermal radiation emits photons randomly with varying energies and directions without coherence.
Ali Javan and his colleagues at Bell Labs constructed the first gas laser later in 1960. They used a mixture of helium and neon to produce continuous infrared light at 633 nanometers.
Robert N. Hall invented the semiconductor laser in 1962. His device was made of gallium arsenide and emitted near-infrared light at 850 nanometers.
The ELI-NP facility in Romania houses the world's most powerful laser as of 2019. It is capable of delivering 10 petawatts of power.