Overseas Students Health Cover (OSHC) is a Medical insurance required by overseas students who require a visa to study in Australia.
It helps to pay towards medical and hospital care, and provides some contribution towards the cost of many prescription medicines, as well as medically necessary ambulance transport.
One of the popular insurers for this is Medibank, and the details of their cover can be seen at this pdf document Medibank OSHC.
As a brief guide to the cover that you may get, one of the examples in the above document states:
Out of hospital medical services:
General practitioners 100% of the Medicare Benefits Schedule (MBS) fee.
The MBS fee for a standard consultation was $34.90 from 1st November 2010. Yet many doctors would charge between $50 and $75.
Based on that, you may pay out $50 or $75 for a consultation, but the insurance would reimburse you with only $34.90.