Mighty Asia, the foremost of all, half again larger than Africa, the next biggest continent in the world1. In olden days it was hardly conceivable that Europe and Asia were in the same world. As far as the East is from the West, the ancients would say, attempting to delineate infinitude. But that was from a cultural point of view. Scientific Geographers prefer the term Eurasia as describing a true contiguous continental landmass. Cultural Sociologists, from who much of our opinions of peoples are formed, have bequeathed to us Asia, and of course, Europe.
The idea of continents has evolved over time; and today it is still rather flexible. The color coded image below is borrowed from wikipedia2.
So how many continents are there? How many colors do you see in the image above?
Most English speaking nations adopt the seven continent system illustrated above. A six continent system, combining Europe and Asia into Eurasia is commonly used in Eastern Europe, Russia and Japan. That same six continent system, modified to a 5 inhabited continent system, is used by the United Nations and the 5 ringed Olympic committee, leaving off Antarctica as being, essentially, uninhabited.