Australia has 3 layers of government- Federal, State, Local.
The States are - Nsw, SA, WA, VIC, TASI, QLD, NT, ACT.
The difference between a territory and a state is in regard to administration and governance.
Australia's six states represent the six British colonies that joined together to create the common-wealth of Australia. In forming the Commonwealth, the states approved a constitution that gave the new Commonwealth government the right to pass laws on certain subjects, and allowed the states to retain all other law-making rights. States have a constitutional right to have a state parliament and pass certain laws.
Land within Australia's national border that is not claimed by one of the states is called a territory, The Northern Territory, the Australian Capital Territory and Norfolk Island are self-governing territories. The Commonwealth passed a law allowing each territory to convene a parliament and make its own law in similar manner to the states.
Under the Australian constitution, state parliaments are allowed to pass laws as long as they do not conflict with national laws. Unlike the states, the territories are governed by national law.