If you are working in Australia your employer will pay a minimum of 9.5% of your earnings into a superannuation fund (retirement savings fund).
Normally you cannot access this money until you reach 60, but temporary residents and visitors on a Working Holiday visa can reclaim their money when they leave Australia.
Companies like Taxback, that specialise in tax refunds for backpackers and temporary residents are able to process the necessary paperwork to allow you to withdraw funds from your super account when you return home from Australia.
Money in your super fund is subject to withholding tax. You are taxed between 0% and 47% on the total value of your reclaimed superannuation when leaving Australia, however there are plans to increase this to 95% from 1 July 2017. Don’t think about leaving your super until the tax rate changes to something more reasonable either, as the total amount of unclaimed super is transferred to the Australian Taxation Office six months after you leave Australia.
The Australian Taxation Office has more information on superannuation.