A continent is one of the world's main continuous pieces of land. (The word continent comes from the Latin terra continens, meaning "continuous land".)
Unfortunately, even the experts cannot agree on how many continents there are:
Curiously, we have a word for somebody who comes from Mars (a Martian), but we have no word for somebody who comes from Antarctica.
This chart lists what is probably the most widely-accepted number of continents (7), and shows the associated adjective and the noun used for a person from each continent:
"Continent" is a geographical term, not political.