When did the Jurassic time period occur?

According to the International Commission on Stratgraphy, the Jurassic period lasted from 199.6 million to 145.5 million years ago. It is the middle period of the Mesozoic ("middle life") Era.

This is the period when the dinosaurs were predominantly present on the face of earth, various species of the same were present everywhere. But an unexplainable event turn things around.