The field of study which focuses on volcanoes, magma and lava is known as volcanology. It also deals with the geophysical, geological and geochemical phenomenon associated with them. Volcanology also plays a vital role in saving lives through predicting the eruptions of volcanoes. Some of the equipment involved in observing volcanoes are seismographs, portable ultra-violet spectrometers and thermometers. Seismographs are placed near volcanoes to detect increased seismic activity, especially long period harmonic tremors. Ultra-violet spectrometers help in monitoring emissions of volcanic gases such as sulfur dioxide. Changes in thermal properties of volcanic vents and lakes are measured using thermometers. This book is a valuable compilation of topics, ranging from the basic to the most complex advancements in the field of volcanology. Those with an interest in this field would find this book helpful. It will serve as a valuable source of reference for graduate and post graduate students.