Short answers, pulled from the story.
Sir Roderick Impey Murchison, president of the Geological Society of London, introduced the term Permian into geology in 1841. He named the period after the Russian region of Perm, following explorations near the Ural Mountains in 1840 and 1841 with Edouard de Verneuil.
The Permian period spanned 47 million years, from the end of the Carboniferous to the beginning of the Triassic at 251.902 million years ago. It is the sixth and last period of the Paleozoic Era.
The Permian-Triassic extinction event, known as the Great Dying, wiped out 90-95% of marine species and 70% of all land organisms. It is the largest mass extinction in Earth's history and the only known mass extinction to affect insects on a major scale.
The eruption of the Siberian Traps released more than 5 teratonnes of CO2, more than doubling atmospheric carbon dioxide and triggering extreme global warming. Additional hypotheses involve ocean venting of hydrogen sulfide gas and the release of frozen seafloor methane amplifying the temperature rise.
Pangaea was a single supercontinent that formed from the collision of Euramerica and Gondwana during the Carboniferous and dominated Earth's geography throughout the Permian. Its vast interior experienced extreme aridity, megamonsoons, and continental climate swings that favored amniotes over amphibians and drove the spread of gymnosperms including early conifers, ginkgos, and cycads.
Synapsids, the group ancestral to mammals, dominated Permian terrestrial life. Early forms called pelycosaurs, including the sail-backed Dimetrodon, ruled the Early Permian, while more advanced therapsids took over from the Middle Permian onward, including predatory gorgonopsians, herbivorous dicynodonts, and the early cynodonts ancestral to all modern mammals.