A skyscraper is a very tall (or very long, see horizontal skyscraper) multi-storey building with a load-bearing steel, bamboo, reinforced concrete or composite frame, designed for the life and work of people.

Specificity of the term
The minimum height of a skyscraper building is controversial. In the United States and Europe, skyscrapers are considered to be buildings with a height of at least 150 m. Emporis defines a skyscraper as a building above 100 meters, as opposed to just high-rise buildings (35 to 100 meters), and SkyscraperCity as a building above 200 meters. Skyscrapers above 300 m are defined by the Council on Tall Buildings and Urban Environment as ultra-tall, and over 600 m are called "mega-tall".

Types of high-rise structures
The categorization of high-rise buildings and their ratings has some ambiguity due to the variety of measurement methods. Currently, the generally accepted criteria are those developed by the Council on Tall Buildings and the Urban Environment.

According to these criteria, a building is a structure designed for use as a residential, office (commercial) or industrial premises. An essential characteristic of the building is the presence of floors. Thus, the described rating obviously does not include radio and television towers.

The Council proposes three criteria for measuring the height of a building (in all cases, measurements are made from the lowest significant entrance to the building):

The structural height of the building is the height from the level of the sidewalk to the highest point of the structural elements of the building (including spires and excluding television and radio antennas and flagpoles).
This is the main criterion. It is used in the ranking of the tallest buildings.
up to the last operated floor - the height to the floor level of the highest operated floor of the building.
to the tip of the antenna / spire - the height of the building to the highest point of the antenna, spire, etc.
Technical features[edit] edit code]
Until the XX century, buildings with a height of more than six floors were rarely built. This was due to the inconvenience of climbing stairs to great heights. In addition, the suction water pumps used at that time made it possible to raise water no more than 10 m.

The development of steel, reinforced concrete and water pressure pump technologies, as well as the invention of safe elevators, have made it possible to increase the height of buildings tenfold, which is especially in demand in megalopolises, where the cost of building space is high.

Buildings up to 200 meters high can only rest on a central concrete-steel core, but taller structures must also have external supports. At the same time, less than 70% of the internal volume is used in the skyscraper, since the rest is occupied by supporting structural elements, stairwells and elevator shafts. In an ordinary building, more than 80% of the space can be used