A fuel gauge is a device found in vehicles that indicates the amount of fuel remaining in the tank. It typically consists of a dial or digital display that shows the fuel level, helping drivers know when to refuel. The gauge works by using a float that moves up and down with the fuel level, sending signals to the gauge to display the current amount. Most fuel gauges are calibrated to show full, half, and empty levels, making it easy for drivers to assess their fuel status at a glance. Some modern vehicles also feature warning lights that illuminate when fuel is low, providing an additional alert to prevent running out of fuel unexpectedly.