Speedometer / ORDOMETER / tachometer

Speddometer
Indicates the vehicle speed in units of km / hour.

Odometer
Shows the total distance has been traveled by a vehicle. And use this pointer for the benefit of periodic maintenance schedule and service.

Tripmeter
To find a specific mileage from one place to another.

Tachometer
Indicate engine rotation / minute, and do not run the car until the engine rotation speed (red line) this can lead to engine damage.