Referencing is giving credit where credit is due. When you reference, you are recognising the work of others and their contribution to the development of your ideas.
Referencing is required in all university study.
Any time you fail to reference, you are claiming your content is all original work and ideas. This is unethical, and contravenes both university and professional standards.
According the Code of Professional Conduct of the Australian Computer Society (ACS), all IT professionals should 'give credit for work done by others where credit is due' (2014, sec. 1.2.3 (f)).
Most of the IT courses will require you to use the USQ Harvard AGPS referencing style. This is not the same as other Harvard styles, though it is very similar.
The official USQ guide to Harvard AGPS. This offers templates and examples of in text citations and reference list entries for this style.
Further information on referencing can be found through the library website.