A set of elements or services required for the operation of an activity, even if they are not part of it. It is composed of the Latin prefix infra_ ( "lower" ) structure. It has aeronautical origin, where it is called 'infrastructure' to everything that is not part of the plane but is indispensable for flight, such as runways, hangars, control towers, then the concept was extended to other areas. See substructure .
