Terminology
Various manufacturers have over time used different terms for airbags. General Motors' first airbag modules, in the 1970s, were marketed as the Air Cushion Restraint System (ACRS). Common terms in North America include nominal role as a supplement to active restraints, i.e., seat belts. Because no action by the vehicle occupant is required to activate or use the airbag, it is considered a passive device. This is in contrast to seat belts, which are considered active devices because the vehicle occupant must act to enable them. Note that this is not related to active and passive safety, which are, respectively, systems designed to prevent accidents in the first place and systems designed to minimize accidents once they occur. For example, the car's Anti-lock Braking System will qualify as an active-safety device while both its seatbelts and airbags will qualify as passive-safety devices. Further terminological confusion can arise from the fact that passive devices and systems — those requiring no input or action by the vehicle occupant — can themselves operate in an active manner; an airbag is one such device. Vehicle safety professionals are generally careful in their use of language to avoid this sort of confusion, though advertising principles sometimes prevent such syntactic caution in the consumer marketing of safety features. In contrast, the aviation safety community uses the terms active and passive in the opposite manner
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