The document provides information about tsunamis. It begins with an introductory statement defining a tsunami as a very large sea wave generated by disturbances along the ocean floor such as earthquakes, landslides, or volcanic eruptions. It then explains that tsunamis occur when a major fault underneath the ocean floor suddenly slips, displacing rock and pushing water above it like a giant paddle to create powerful ocean waves. These waves travel across the ocean until reaching the coastline, where their height increases as they reach the continental shelf and wash ashore, often with disastrous effects such as severe flooding, loss of life, and property damage.