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If you look at a triangle, it has three points, right? That's essentially triangular trade -- except the points are ports where ships check in to either take on cargo or deliver what they have. The lines connecting them are the routes. For example, the slave trade had three major destinations: Africa - to pick up slaves North America - to deliver a portion of them to the markets there in exchange for goods Caribbean - to deliver the rest before heading back to Africa to repeat the whole thing over again using the profits gained from stopping in North America and the Caribbean. Of course, the ship could opt to stop in either the Caribbean of North America, but the important thing to remember is that the slaves were traded for goods that would eventually head back to Africa to keep the trade going.