Volcanic processes are not only disasters that bring death. Their upbuilding role became apparent. Mountains, ridges, islands in the oceans are born in the fire of volcanoes. Volcanoes provide the key to knowing the life of the depths of the Earth, to studying the riches of its bowels. The study of these formidable phenomena made it possible to predict them, to develop measures to protect against them. The book is intended for students of folk universities of natural science knowledge.