Geothermal energy is the heat energy contained within the Earth which generated geological phenomena on a planetary scale. Today the term is used to refer to the Earth's heat that could be recovered and exploited by man. This type of utilization is in a variety of forms and requires differing methods of recovery depending on the specific situation. This text explores the present understanding and utilization of geothermal energy. Focusing on a variety of applications, the contributors each develop a specific area relating to the potential of geothermal energy and its effects on a community. They give a detailed exploration of developing fields and show how cost effective geothermal energy would be given the right conditions and effective recovery systems.