Proactive and reactive safety features.

Elmer Berger is usually credited with inventing the rear-view mirror, though in fact he was the first to patent it (1921) and develop it for incorporation into production streetgoing automobiles by his Berger and Company.

Some consider the creation of the rear view mirror a minor innovation.  The safety it provided during the development of the automobile is crucial, why I believe it deserves noting.  Now we have back up sensors, cameras with those features not beeping or sending alerts to drivers for caution.  The creation of the seat belt dominates in the safely features developed in vehicles, then the airbag but it is the small things that are important because keep in mind the mirror was to prevent accidents as the seat belt and air bag were desisigned for when you got into an accident.  Proactive and reactive.

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