This International Standard defines terms corresponding to, and gives guidance for the classification of, mobile and self-propelled machinery used in forestry and related operations. Both the definitions and the classification have been determined according to the end use of the machines as intended by the manufacturer. The terms and definitions do not cover all possible forestry and related operations or machinery, nor do they describe specific machines, but are given as an aid to nomenclature. This International Standard is applicable to machines designed for use in forestry for site preparation, planting, harvesting, processing, and the transport of wood and wood fibre. It is not applicable to machines designed to be used exclusively in sawmills or wood yards, to on-highway transport vehicles, or to aerial vehicles.