Not all enumerated powers are the exclusive powers of the federal Parliament. The power to make laws in many of the areas listed in section 51 of the Constitution is shared with the states (concurrent powers). The powers listed in sections 52, 86, 90 and 122 are all exclusive to the federal Parliament; these powers are not shared with the states.
The federal Parliament is also able to make laws beyond its enumerated powers. The authority to make these laws may be the result of judgments of the High Court of Australia (see the Income Tax (Wartime Arrangements) Act 1942) or convention (tradition).