The "Columbian Exchange" refers to the exchange of goods between the old and new worlds after Columbus' travels. While his "discovery" of America is up for debate, he is credited with opening up the Atlantic trade routes that would impact nearly every part of the world. This massive exchange of foods, ideas, and diseases resulted in both positive and negative effects. For example, Europe and China experienced major population increases due to the new world crops that quickly became staple items for these old world areas. However, native populations in the new world were nearly wiped out due to their lack of immunity to old world diseases.