Hood scoops are not necessary technology for automobiles to have but they can enhance a car’s performance if designed properly. Many performance cars use hood scoops for just that reason.
The way that hood scoops work is actually pretty simple, but not widely known. An engine gets oxygen from the outside air. Cool air is denser than hot air and thus has more oxygen in it, which produces more power when it burns. Since the air in the engine compartment is usually considerably hotter than the outside air, if the engine takes its intake air from under the hood, its power output will be reduced. The solution is allow the engine to breathe cooler, denser outside air, such as from a hood scoop.