If you are over 18 and earn more than $450 before tax in a calendar month your employer must contribute a portion of your salary into superannuation. The amount that is contributed to superannuation is call the superannuation
guarantee. For the financial year ending 30 June 2019 this percentage is 9.5%. It will increase to 10% from 1 July 2020.
https://www.ato.gov.au/rates/key-superannuation-rates-and-thresholds/?anchor=Superguaranteepercentage#Superguaranteepercentage
If you annual salary was $100,000 then your employer would need to contribute $9,500 to your superannuation.
As there are tax incentives for superannuation contributions each year you can contribute up to $25,000 (in 2019) into superannuation from pre-tax income. Superannuation guarantee contributions made by your employer are
included in the $25,000. Contributions greater than $25,000 per annum attract tax at high tax rates which is designed to limit the size of super funds and prevent tax avoidance by the very wealthy.
It is possible to “carry forward” unused portions of the annual $25,000 cap if you have a superannuation balance below $500,000 and make larger contributions in future years. This flexibility can make it easier for people to save
for retirement if they have interrupted work patterns.