What divides the continents?

Each continent is on a plate that is divided from the next by a fault line. At that fault line magma exudes to the surface and flows on the bottom of the ocean usually, as the plates drift apart. If on the other hand they are drifting together, one plate will slide under the other as they move. America is drifting West as Africa drifts East at a fault line in the bottom of the Atlantic Ocean.