The term of volcano is familiar to most people, but few people have actually seen a volcano eruption with their own eyes. Mysterious and unfamiliar volcanoes have always been natural phenomena studied and explored by humans.
    More than 2,000 years ago, the famous geography book Shan Hai Jing described a kind of mountain of flames in the mountains in western China, which refers to volcanoes. The word volcano contains the meaning of burning mountain.
    In ancient Europe, there is still a myth about volcanoes. There is a small island in southwestern Italy. Someone once saw a volcanic eruption, thinking that something was burning underground, and it was said that Vulcan was pulling the bellows there To burn his iron furnace with smoke and fire. Later, the iron furnace became a mountain, and the ancient Romans called the island and the mountain volcano. Since then, Europeans have referred to volcanoes. Nowadays, the pronunciation of volcano in English, Russian and other languages is volcano.
    In ancient times, because people did not fully understand various phenomena in nature, volcanoes were cast in a mysterious color.
Volcano is a geological phenomenon. It is the hot magma from the deep part of the earth that erupts out of the surface, and its temperature can be as high as 800℃～1200℃, and it becomes rock after it condenses. The eruption of a volcano is accompanied by a large amount of gas, dust and rock fragments. These debris and overflowing magma gradually accumulate into mountains, which are called volcanoes. The volcano does not burn with the dazzling light emitted by the hot magma, which is the same as the dazzling light emitted by the hot molten iron from the iron furnace.
T    here have been many volcanic eruptions on the earth since ancient times. Volcanoes that are still erupting or have erupted in historical records are called active volcanoes; volcanoes, which have erupted in the past and ceased with historical records, are called dormant volcanoes: human history has erupted before but is no longer active. Indications, volcanoes that can no longer erupt in the future are called extinct volcanoes; they have a longer history of formation. Volcanoes whose faces are hard to recognize are called ancient volcanoes. The time limit for delimiting active volcanoes varies from country to country. The most common limit, which is that volcanoes that have erupted in the past 10,000 years, are called active volcanoes, while some countries regard volcanoes that have erupted in the past 2000 years as active volcanoes. Dormant volcanoes belong to the category of active volcanoes. They are more dangerous than erupting volcanoes. On June 9th , 1991, Mount Pinatubo in Luzon revived after being dormant for more than 600 years and suddenly erupted violently. Because volcanologists accurately predicted the time when the volcano was about to erupt. The residents of Manila, where there are 2 million residents, were evacuated safely, avoiding a disaster. Over the past 10,000 years, there have been no less than 1,343 volcanoes that have remained active on the earth. Some of them have erupted several times or even dozens of times. In the past 2000 years, there have been more than 5,000 independent volcanic eruptions. There are more than 50 eruptions every year.