It's reflected in contemporary artwork and population migration and linguistic changes, but we're going to focus, as we so often have during Crash Course, on trade. So the world today, as symbolized by our international felt melange, experiences widespread global economic interdependence. Now, of course, economic interdependence and the accompanying cultural borrowing are nothing new. You'll remember that we found trade documents from the Indus Valley civilization all the way in Mesopotamia. But for a few reasons, the scale of this trade has increased dramatically. One, multinational corporations have global reach and increasing power. Two, travel and shipping are cheap and safe.