Oceania is a continental region between Asia and the Americas. The Australian mainland is the biggest landmass and there are around 10,000 islands to its east. Oceania's border is defined in part by Australia, but mainly by surrounding ocean and seas rather than one single landmass like other continental regions. Oceania is also the smallest continental region in land area and the second smallest, (after Antarctica), in population. It is composed of four regions: Australasia, Polynesia, Melanesia, and Micronesia.

Australasia includes Australia and New Zealand and is by far the biggest region. To put this in perspective, New Zealand is bigger than all the other South Pacific Islands combined and New Zealand fits into Australia nearly 30 times.

New Zealand is also culturally and linguistically part of Polynesia, and is the south-western anchor of the Polynesian Triangle of which Hawaii and Easter Island make up the other points. Other countries in Polynesia include: French Polynesia, Cook Islands, Samoa, and Tuvalu.

Nearby Melanesia includes New Caledonia, Solomon Islands, New Guinea, Vanuatu, and Fiji and is culturally and racially distinct from Polynesia.

Micronesia to the north is also distinct. Island nations here includes Kiribati, Guam, Marshall Islands, Federated States of Micronesia, Northern Mariana Islands, Palau, Nauru, and Wake Island.