Hot spring is a kind of spring water. Strictly speaking, it is natural water gushing out of the ground. The natural outcrop of groundwater whose temperature at the spring mouth is obviously higher than the local annual average temperature but lower than (equal to) 45 degrees is called hot spring, which contains mineral water with trace elements beneficial to human health. However, from the perspective of fuzziness, there are also hot springs in the proportion of underground extraction and artificial heating.

The transverse temperature of hot springs generally exceeds 20℃. Springs whose water temperature exceeds the local annual average temperature are also called warm surface springs. Most of the water in hot springs comes from precipitation or surface water penetrating deep underground, which absorbs the heat of surrounding magma and then rises and flows out of the surface, usually mineral springs. A boiling spring whose spring temperature is equal to or slightly higher than the boiling point of local water; Hot springs that can spray water periodically and rhythmically are called geysers. There are more than 2,400 known hot springs in China. There are many hot springs in Taiwan Province, Guangdong, Fujian, Zhejiang, Jiangxi, Yunnan, Tibet, Hainan and Fuxin, among which Yunnan has the most, with more than 400 hot springs. Tengchong's hot springs are the most famous, with a large number, high water temperature and rich sulfur. The best hot spring sodium bicarbonate in China is distributed in Conghua in the south and Fuxin in the north.

The world-famous geysers are mainly distributed in Iceland, Yellowstone National Park in the United States and Taupo, the North Island of New Zealand.

Strictly speaking, hot springs are natural water that gushes from the ground and the water temperature is higher than the local surface, and is pumped from the ground. Can't call it a hot spring. At present, artificial hot springs have been heated and added with a certain chemical ratio to meet the needs of different people. So from the perspective of fuzzy concept, there are three kinds of so-called hot springs at present, including natural spewing type, artificial extraction type and artificial heating ratio type.