When you are driving, sometimes you want information about your trip so you can gauge the efficiency of your vehicle and plan for refueling stops. A trip computer helps you determine this information.
A trip computer is a device either installed when your vehicle was manufactured or as an aftermarket accessory. It measures speed, the miles per gallon at that speed, the number of gallons of fuel left in your tank and how many miles left before needing to refuel. Some trip computers can also gauge the amount of time you spent driving on a particular trip and the amount of time left before you run out of gas.
Depending on the make, model, and year on your car, the trip computer will have different capabilities. On inexpensive cars, your trip computer may only include an outside temperature gauge and fuel mileage information. In high-end, luxury cars, trip computers are often more advanced; for example, some can monitor overall efficiency for separate drivers or monitor tire pressure.
Some on-board trip computers also notify the driver if the vehicle is due for maintenance. For example, the computer can display the number of miles left until an oil change is due, and then display a message when it is time for service.