Despite numerous changes on how commerce transformed throughout the years of 650 C.E. to 1750 C.E., there were a few continuities in which remained constant. One of these factors is the use of the trade routes. Trade routes from 650 to 1750 have remained the same throughout no matter what was being traded, or who someone was trading with. The key reason to understand for this consistency is the fact that countries MUST import and export, and the Indian Ocean was an ideal place for constant importation and exportation. Few methods signal the idea of using the same trade routes. From 650 to 1750 the predictable monsoon winds were used in a way to make travels across the Indian Ocean easier. Also, from the beginning of using the Indian Ocean as a place of commerce, merchants and other people involved in trade always entered the same ports and cities. The reason for consistency is because these merchants know how to get there because of using the same route so repeatedly and the merchants also know that the people being sold the products to are a reliable source for profit. Goods of export and import have also been included in this continuity because these goods have always been traded. These goods include: metals, like silver and gold, textiles, and a vast assortment of crops.