This document provides information about earthquakes, including what causes them, how their effects vary, and how they are measured. It discusses that earthquakes are caused by movements in the earth's crust along plate boundaries. The magnitude of earthquakes is measured using seismometers, and their effects depend on factors like the quake's strength, population size, and development in the impacted area. It also lists some of the most earthquake prone locations like China, Chile, Turkey, Japan, and Indonesia.