Wikipedia facts
Water supply and sanitation has been a primary logistical challenge since the dawn of civilization. Where water resources or infrastructure or sanitation systems are insufficient for the population, people fall prey to disease, dehydration, and in extreme cases, death.
Major human settlements could initially develop only where fresh surface water was plentiful, such as near major rivers. Over the millennia, technology has dramatically increased the distances across which water can be relocated, but the availability of clean and fresh water remains a limiting factor on the size and density of population centers, and is expected to remain so into the foreseeable future.
Źródło: https://en.wikipedia.org/wiki/History_of_water_supply_and_sanitation
Boiler - a definition from Wikipedia
A boiler is a closed vessel in which water or other fluid is heated. The fluid does not necessarily boil. (In North America the term "furnace" is normally used if the purpose is not actually to boil the fluid.) The heated or vaporized fluid exits the boiler for use in various processes or heating applications,12 including water heating, central heating, boiler-based power generation, cooking, and sanitation.
Źródło: https://en.wikipedia.org/wiki/Boiler
Water leak at home
When we find that in the house there is a water leak, the cause of which we can not define ourselves, we should immediately call a plumber. It is also important that we immediately shut the main water valve that shut off the water supply to taps and various water bodies existing in the home, and thus we prevent its further flooding. In new homes closing the main valve is not a problem, but in the case of older homes may be harder for us to determine which of the existing valves is the main water valve and an additional difficulty may be the same turn. In such a situation called our plumber will also replace the old water valve installed in our house.