Non-concessional contributions are able to be made to your account from your after-tax income and are not taxed when entering the fund.
There is a non-concessional contribution cap of $110,000 per financial year. You can read more here.
Concessional contributions are taxed at a 15% rate and are made to your account from pre-tax income. These contributions include those made by employers from your pre-tax income and self-employed people who may wish to make contributions from their pre-tax income and claim a tax deduction for those contributions. Members of other types of employment can also make personal concessional contributions.
The general concessional contributions cap is $27,500 per financial year. You can read more here.