The Nazca Plate (under the Pacific Ocean) is currently sliding under the South American Plate, which is not always a smooth process. This plate boundary created the Andes Mountains, millions of years ago, and continues to create earthquakes in Chile today. These earthquakes can also cause tsunamis that destroy coastal cities and towns.
One of the most important parts of Chile's earthquake preparation is the architecture. Many Chilean buildings are now designed to sway with the force of the earthquake instead of trying to resist it, which prevents them from collapsing. The building I live in is also made of concrete and plaster, which are stronger materials that can resist small tremors and even bigger quakes. After all, the only sign of the 2010 earthquake in this house is a tiny crack in the wall!
Chileans are also very well prepared for tsunamis, with evacuation plans and warning systems. Every coastal city I've visited in Chile has signs pointing the way to higher ground in case of a tsunami, even in places that don't look like they are very near the water. The government also has a good warning system for both earthquakes and the tsunamis that often follow them, sending messages out through different media systems, including texts sent directly to Chilean citizens' cell phones.
Every major earthquake in Chile is a chance to improve the emergency response compared to the previous one, and most Chileans responded faster and better to the quakes in 2014 and 2015 than in 2010. Chileans are earthquake experts, surviving and recovering from quakes that would destroy other countries. Living so close to a tectonic plate boundary, they have to be!
