Our Sun pulsates with millions of modes of vibration that allow acoustic waves to probe its interior. Helioseismology is a set of tools that measures and interprets these oscillations, analogous to terrestrial seismology.  Local helioseismology aims to make tomographic images of the solar interior at high spatial and temporal resolution that involves cross-correlation techniques, hydrodynamic modeling, and inversion methods.  Obtaining three-dimensional images over long periods of time of sub-surface conditions should help us understand unresolved problems such as the dynamo, sunspots, and energetic events.  I will review properties of the Sun and how solar seismic data is obtained, the procedures that go into its analysis and interpretation, and give a selection of exciting results.