A tsunami is a series of enormous ocean waves caused by earthquakes, volcanic eruptions, or landslides. Tsunamis can be very destructive when the waves reach land, destroying coastal areas and infrastructure. In 2004, a massive tsunami in the Indian Ocean was triggered by an earthquake and killed over 250,000 people across 11 countries, making it one of the deadliest natural disasters in history. To help prevent loss of life from future tsunamis, it is important to educate people on tsunami risks, have early warning systems in place, and ensure coastal evacuation plans are followed when needed.