An "Extinction Event" refers to a significant and rapid decrease in the biodiversity of Earth, where a large number of species become extinct in a relatively short period. These events can be caused by various factors, including catastrophic environmental changes, climate shifts, volcanic eruptions, or asteroid impacts. The most famous extinction event is the Cretaceous-Paleogene extinction, which led to the demise of the dinosaurs around 66 million years ago. Extinction events can have profound effects on ecosystems, leading to the loss of species and altering the course of evolution. After such events, surviving species often diversify and fill the ecological niches left vacant. The study of extinction events helps scientists understand the resilience of life and the factors that contribute to biodiversity loss, which is increasingly relevant in the context of current human-induced extinctions.