Employers are required to pay most employees 9% of their income as a superannuation contribution (superannuation guarantee contributions). But, most people can make additional contributions in excess of the 9% (ie a salary sacrifice contribution).
Making a salary sacrifice contribution into your superannuation fund may be a tax effective way to reduce your personal taxable income and as such reduce the personal tax you pay. Salary sacrifice contributions are taxed at 15% on entering your superannuation fund and must stay in superannuation until you reach preservation age (currently in excess of age 55).
This strategy will not be right for everyone, so please seek financial advice first.