You will require this authorisation if you intend to teach unlicensed people to drive motor vehicles for financial gain or in the course of any trade or business. It does not authorise you to teach people to drive a motorcycle, a vehicle with a gross mass of more than 4.5 tonnes, or a vehicle with a seating capacity of more than twelve adults including the driver.
If you are currently an accredited driving instructor in another state or territory in Australia or New Zealand then you may be eligible for mutual recognition. Mutual recognition allows a skill or training to be recognised Australia-wide and aids the application process.