The document summarizes information about tsunamis. It defines a tsunami as a series of waves generated by the rapid displacement of water on a massive scale, which can be caused by earthquakes, landslides, volcanic eruptions, and meteorite impacts. The effect of tsunamis can range from unnoticeable to devastating. It notes that while tsunamis pass unnoticed in deep ocean waters, they take on characteristics of violent tides as they approach land. The document provides both general information about tsunamis and answers specific questions about tsunami causes, effects, terminology, and behavior in deep versus shallow waters.