Definitions:
Seismology (from the Greek seismos = earthquake and logos = word) is the scientific study of earthquakes and the movement of waves through the Earth. Seismic waves produced by controlled explosions or vibrating sources are the primary method of underground exploration.
Geophysics is the study of the earth by quantitative physical methods, especially by seismic, electromagnetic, and radioactivity methods.
This interactive Seismic Overview is a picture-based explanation of seismic data — how the data are gathered and how the data are used. There are 40 slides that run in their own custom-sized window, and each one should take only about 30 seconds to read and digest.