Modern acrobatic kites use two or four lines to allow fine control of the kite's angle to the wind. Traction kites may have an additional line to de-power the kite and quick-release mechanisms to disengage flyer and kite in an emergency.

Kites have been used for scientific purposes, such as Benjamin Franklin's famous experiment proving that lightning is electricity. Kites were the precursors to aircraft, and were instrumental in the development of early flying craft. Alexander Graham Bell experimented with very large man-lifting kites, as did the Wright brothers and Lawrence Hargrave. Kites had an historical role in lifting scientific instruments to measure atmospheric conditions for weather forecasting.

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