Triple-Zero

Triple-Zero (000) is the national emergency number within Australia. If someone has an emergency situation that is life threatening or time critical, this number will connect them to a Telstra operator who will then connect them to the police, fire or ambulance service as required. 112 is a secondary emergency number that will direct calls to the Triple Zero answering point. It is against the law to use this number if there is no emergency. 
History.
Before 1961, Australia did not have a national number for emergency services; each of the different emergency branches (police, fire department or ambulance) had their own number. In 1961, the Postmaster General (PMG) introduced the Triple Zero (000) number in most of the major Australian cities and by the end of the 1980s it had become nation-wide. The number Triple Zero (000) was chosen for several reasons, one of which was that it was easy to dial in darkness because the number zero was next to the finger stop on most Australian telephones.
Possible uses.
A person would dial Triple-Zero (000) if they require a response from police, fire or ambulance for life threatening or time critical events.
Procedure.
When Triple-Zero (000) is dialled, a Telstra operator will answer and ask the caller the following: “Emergency, police, fire or ambulance?”. The Telstra operator will then connect the caller to the required emergency service. The emergency service call taker will then ask the caller further, and send assistance as required.