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An earthquake is defined as a movement of the ground surface which can range from a quaint, negligible tremor to a wild shaking capable of great destruction. Geographically, it can be understood as a form of energy wave motion transmitted through the surface layer of earth in widening circles from a point of sudden energy release called the focus. The intensity or the magnitude of the earthquake is measured on the Richer Scale. The world's most intensive earthquake measured until now has been 9.5 on the Richer Scale. As said earlier, the place of the origin or the place of the energy release is called the focus which is usually below the surface. The place perpendicular to the focus on the ground surface is called the epicenter. The seismic waves move away from the epicenter. Hence, an instrument to record the seismic waves called seismograph. The main reason behind the occurrence of an earthquake is the disequilibrium in the earth's crust. This disequilibrium can be caused by volcanic eruptions, faulting and folding, hydrostatic pressure of man made water bodies such as reservoirs and lakes, and by the movement of the plates. The earthquakes in India along the Himalayan range and its foothills are caused by the shifting of plates. The Asiatic plate is moving southwards whereas the Indian plate is moving northwards. This causes the Indian plate to be subducted below the Asiatic plate. This collision and folding causes earthquake in North of India as well as Tibet and Nepal. This earthquake belt encompass the Sulaiman and Kirthar Shear Zones in the west to the Himalayan in the north and the Burmese arc in east. The intensity of an earthquake is determined by the the scale reading on the Richter or Mercalli scales. An earthquake becomes a disastrous one only when it occurs in an inhabitant area.