Tsunami is a series of giant waves. In Japanese, tsunami means 'Harbor Wave'. A wave is created when energy passes through water. Moving air or wind provides energy to water, forming regular waves. While on the ocean floor, when a tectonic plate suddenly slides beneath the other, the resulting earthquake releases tremendous amount of energy. This energy spreads outward from the point of earthquake, triggering waves that can form tsunami. Initially, these waves are small in size but they travel at great speeds. However, when the waves approach the shore, the rising seabed obstructs the energy of waves. This slows down the speed of waves. But the energy flux must remain constant leading to an increase in height of the waves, thus resulting in tsunami.