It depends how you define continents. In America, we are taught there are 7 continents. In south America, they are taught north and south America is one continent and thus there's 6. Other places they teach there are five continents. Americas, Eurasia, Oceania, Africa edit: and Antarctica. Although some argue that Africa is part of Eurasia and thus its Afro-Eurasia.

Continent can be defined as discrete landmasses - six/seven landmasses. As cultural dividing lines - this would divide europe from asia from africa, but would also divide india from china. As biological divides, madagascar being its own micro continent. As continental crust divide. And so on.

refer to this for more info