High beam: Also called main beam, which comes from the main filament of the head light and is of the higher intensity, to be used while driving at night on poorly lit roads with very less traffic.

Helper spring: These are provided on many commercial vehicles in addition to the main springs. They serve to increase the range of loading, keeping the stiffness of the suspension within allowable limits.

Head restraint: It is meant to protect the occupants of front seats from whiplash injury of the neck in case of a rear impact. It is usually fixed into the top of the seat back and is adjustable so that the top is at the eye level of the passenger.

Hazard Flasher: Blinking lights meant to indicate hazard e.g. the vehicle stopped in or alongside moving traffic, a slow moving vehicle in high-speed lane.

Hatchback: A car with a rear tailgate. Not a saloon or an estate, but something in between, e.g., Maruti 800.

Handling: Relative ability of a vehicle to negotiate curves and respond to road conditions.

Half-shaft: A shaft transmitting the drive from the final drive unit to the road wheels.

Ground clearance: The gap between the lowest point of a vehicle body and the ground.

Grand tower: Larger, more powerful and heavier than sports cars, these vehicles typically have a FR (Front engine, Rear Wheel drive) layout and seating for four (2 + 2).

Gradeability: The ability of a vehicle to climb a grade at a given speed. For example, a vehicle with 5% gradeability at 60 kph is the one which can maintain a speed of 60 kph while going up a slope of 5%.

Glove box: A small compartment located in the dash board on the passenger side for placing small items, such as, owner's manual, vehicle papers, first-aid kit, etc.

Gran Turismo (GT): A car combining the features of the sedan as well as the sports car. Gear Box. A mechanical device to multiply the engine torque by using a system of gears. Gear Ratio. The ratio of turning speeds of the gears.

Gross Vehicle Weight Rating (GVWR): Also referred to as GVW, it is the maximum total vehicle weight (measured at the tyre-ground interfaces) for which the vehicle possesses components adequately rated to safely carry. It includes the weight of the vehicle, fuel, fluids and full pay load. It cannot exceed the sum of all GAWRs.

Global Positioning System (GPS): A system to locate a vehicle using satellite signals.

Gross Combination Weight Rating (GCWR): Entire weight of a vehicle at the ground with a trailer or trailers including vehicle, equipment, driver, fuel and payload (everything that moves with the vehicle)