Executive, Legislative, and Judicial government.
In Australia, the law is managed by three different entities:
Parliament - Who have the power to change laws
The Executive - This is the Queen (or her representative, the governor general), the Prime Minister, and Ministers. The executive have the power to put laws into action (meaning they sign them off and make them enforceable)
The Judiciary - who enforce the law. This is made up of the high court, and other courts.
These three types of government exist at both the State AND the Federal level.