How do impacts by comets and asteroids influence Earth's geology, its atmosphere, and the evolution of life?

A comet is a celestial body made up of ice and dust and assumed to have a tail.

As per considering ancient history, they are even termed as death-dealers and have doomed many planets.

If we talk about Earth, comets and asteroids have played a massive role in changing Earth's geology, atmosphere and evolution. Its believed that dinosaurs population is wiped out from Earth because of comets that falls during that time. Many new diseases are even brought by them.

Large comets can result into global environmental damage and can even lead to mass extension. The dust from the impact and the heat creates many harmful oxides resulting into acid rain and can kill thousand of organism.