(I)Although often referred to as tidal waves, a tsunami is not a usual wave which is only much bigger. (II) People unaware of the danger may remain at the shore for collecting fish from the exposed seabed. (III) Instead it is an endlessly onrushing tide that forces its way through any obstacle. (IV) Most of the damage is caused by the huge mass of water behind the initial wave front. (V) The sheer weight of water is enough to pulverise objects in its path, often reducing buildings to their foundations.