Earthquakes are caused by the sudden release of energy from the breaking of rocks, usually along faults. The elastic rebound theory explains how stress builds in rocks until rupture occurs, releasing energy in waves. The focus is the point where faulting begins underground, and the epicenter is the point directly above on the surface. Seismographs can record earthquake events and locate their origin. About 80% of earthquakes occur in the circum-Pacific belt due to plate tectonics, with the remaining occurring in other belts or within plates. Major earthquakes can cause damage through building collapse, fires, tsunamis, and ground failures.