Pay As You Go (PAYG) is the basic tax taken out of your employees’ salary or wages. The amount of PAYE you deduct depends on your employee’s tax code.
PAYG employees must complete a Tax Declaration form as soon as they start working for you. If an employee fails to complete the tax code declaration, you must deduct PAYG at the no-declaration rate.
The ATO provides PAYG information at: http://www.ato.gov.au/businesses/pathway.asp?pc=001/003/079