Non-residents pay tax on most Australian source income. They pay tax on every dollar of taxable income as declared on their tax return but do not pay Medicare. Residents have to declare all income earned in and out of Australia.
A tax-free threshold of $6000 is available to them and a resident may be entitled to claim some tax offsets (rebates) that are not available to non-residents. Depending on their income, a resident may also have to pay the Medicare levy and Medicare levy surcharge.