Today I found out why Greenland is an island and Australia is a continent.
There are several different ways of thinking about how many continents there are, with models ranging from 4 to 7 continents. However, in most English speaking countries, as well as other nations around the world, the 7-continent model is taught. Using this model, the continents of the world in order of size (descending) are: Asia, Africa, North America, South America, Antarctica, Europe, and Australia.
One of the biggest differences between Australia and Greenland, other than their obvious climate differences, is population. Australia has over 22 million inhabitants, making it the 55th most populous nation in the world. Greenland, on the other hand, has just over 57 thousand inhabitants, making it the 205th most populous nation in the world. However, if population determined continental status, Antarctica would not be considered a continent, either.