What is Great Southern California Shakeout and why did people in Southern California go through this exercise?

The Great Southern California ShakeOut is a region-wide earthquake preparedness exercise designed to enhance community readiness for a major seismic event. Participants, including schools, businesses, and government agencies, simulate their responses to a hypothetical large earthquake, aiming to practice safety protocols and improve coordination. This annual event raises awareness about earthquake risks and encourages individuals and organizations to develop emergency plans and supplies, ultimately fostering a culture of preparedness in the earthquake-prone region.