The Physics of Tsunamis examines tsunamis as a series of surface long waves in the ocean generated by an impulsive geophysical disturbance that abruptly, vertically displaces the ocean water column. This course discusses earthquakes, submarine landslides, and volcanic eruptions that are considered as the most possible sources of tsunami excitation in the ocean. During its propagation from the source to coastal regions far away, the wave speed may or may not be influenced by ocean topography or ocean water characteristics. In this context, class discussions include shallow-water and deep-water approximation, non-dispersive and dispersive tsunamis, and time and spatial analysis of a tsunami wave arrival at shorelines. Tsunami hazard analysis is also discussed, emphasizing on important aspects of tsunami mitigation.