A typical person knows how many gallons their gas tank can hold, and thus how far they can go without needing to refuel. For day to day driving, it doesn't rea

A typical person knows how many gallons their gas tank can hold, and thus how far they can go without needing to refuel. For day to day driving, it doesn't really matter. For long road trips, it can be essential if you're on an extended barren interstate highway.