From a geographic point of view, what's the main difference between an "island" and a "continent?" Don't they both float on the ocean?

Native speaker’s answer
Rebecca
The main difference is that an island typically belongs to or is one country and is smaller than a continent. A continent has specific geographical boundaries and is bigger than an island. Ex: New Zealand is an island. Ex: Australia is a continent due to its size, although it seems similar to an island since it's surrounded by water.