There are two kinds of discrimination that are against the law, direct and indirect discrimination.
Is when someone is treated unfairly because of their age, sex, race, carer's responsibility, disability, homosexuality, marital status, HIV/AIDS or Transgender status compared to someone else who does not have those characteristic, in the same or similar circumstances.
For example, if a real estate agent tells an Aboriginal person they have no properties for rent but tells a Caucasian person that they do, this may be direct race discrimination.
Is when there is a requirement or rule that is the same for everyone but in effect disadvantages people from a particular group more than people from other groups - unless the requirement is reasonable in the circumstances.
an employer says that they need a person over 180cm tall to do a certain job, which could indirectly discriminate against women and some ethnic groups (sex or race discrimination);
a qualifying body excludes everyone with diabetes from registration on safety grounds, which could indirectly discriminate against individuals whose diabetes is controlled and would not impede them from doing the job safely (disability discrimination).