Multistory building taller than the maximum height people are willing to walk up, thus requiring vertical mechanical transportation.
The introduction of safe passenger elevators made practical the erection of buildings more than four or five stories tall. The first high-rise buildings were constructed in the U.S. in the 1880s. Further developments were made possible by the use of steel structural frames and glass curtain-wall systems. High-rises are used for residential apartments, hotels, offices, and sometimes retail, light manufacturing, and educational facilities. See also skyscraper .