In a deployment event, the sensing system sends an electrical signal triggering a release of gas from the inflator. Gas from the inflator fills the airbag causing the bag to break out of the cover and deploy. The inflator, the airbag, and related hardware are all part of the airbag module.
Frontal airbag modules are located inside the steering wheel and instrument panel. For vehicles with roof-rail airbags, there are airbag modules in the ceiling of the vehicle, near the side windows that have occupant seating positions.
Chevrolet Cobalt Owners Manual. Control of a Vehicle
The following three systems help to control the vehicle
while driving — brakes, steering, and accelerator. At
times, as when driving on snow or ice, it is easy to ask
more of those control systems than the tires and road
can provide. Meaning, you can lose control of the
vehicle. See Traction ...