There are two main types of truck: those that can be used to transport goods (goods service vehicles) and those used for towing services (vehicle recovery).
All trucks (no matter what type of service they are used for) must meet certain standards and rules for their class.
Goods service vehicles transport goods. 'Goods' are defined in the Land Transport Act 1998, with a fuller definition provided in the Carriage of Goods Act 1979, and include:
goods, baggage and chattels of any description
animals and plants
money, documents and all other things of value.
Vehicle recovery services tow or carry motor vehicles on a road – regardless of the size or design of the vehicle, and whether or not the towing or carrying is done by the person intending to repair the vehicle.
You can find out more about vehicle recovery services in section 10 of the Operator Licensing Rule.