Seismic Focus: In the inner part of the Earth from where the earthquake originates or the place from where the energy begins to be emitted, is called the Seismic Focus. From this place the energy reaches the Earth’s surface, moving in different directions in the form of waves.
Epicenter: Located above of the seismic focus (at 90° angle), on the earth’s the first place where earthquake waves reach is called the epicenter. It is located at the closest distance from the seismic focus.