But even though Islamic people made a lot of money from trade, most people in the Islamic Empire were still farmers or herders. You couldn't farm efficiently enough to feed very many people who weren't farming, so most people had to farm. The Islamic Empire was great for farmers. Some of that money from conquering people and from trade went into building new irrigation systems and new canals that helped farmers get more out of their land. And the money from trade also helped farmers get through a bad year, or even a number of bad years in a row.
In the late 1400's AD, Portuguese explorers figured out how to sail around Africa and get to India. Even though it was a long trip, it was profitable because they didn't have to pay the middlemen traders in the Islamic kingdoms. Soon most of the trade between China and India and Europe went by sea, around Africa, instead of over the Silk Road through West Asia. This was good for Europe, but very bad for West Asia.
As under Persian or Sassanian rule, the economy of West Asia during the Islamic period depended very heavily on trade. In the north of the Islamic Empire was the Silk Road, running across China, Tajikistan, Uzbekistan, Iran, Iran, and Syria to Lebanon, the Byzantine Empire, and across the Mediterranean to Italy. There wasn't really a road. It was just the track people went along. It led through deserts and over very high mountain passes, so it was a difficult and dangerous route.
As the name implies, silk was a very important part of what was traded along the Silk Road. But other things also traveled – from China, cotton cloth, paper, furs, lacquer work and jade. From Africa, the Mediterranean and West Asia, traders carried gold, silver, ivory, glass, and jewels.
The Silk Road first began during the Chinese Han Dynasty (the Parthian and Roman period in West Asia, about the time of Jesus). People all along the route soon realized they could make more money by producing the goods themselves, than by buying them. So by the 400's AD the Chinese were blowing their own glass. In the 500's AD, West Asians began to produce their own cotton (and sold it to the Romans and around the Mediterranean). By about 650 AD, Romans had learned how to produce silk. And in the late 700's AD, people in the Abbasid Empire began to produce their own paper. But trade continued all along the Silk Road anyway. The Mongol conquests of the 1200’s AD helped a lot by making one big empire out of China, India, West Asia, and all the land in between.
Traders in the Islamic Empire also controlled another very rich trade route from India to Egypt through the Arabian Peninsula. Most of these traders went by sea, taking advantage of the monsoon wind patterns to sail their ships. From the Mediterranean and Africa, these traders brought gold, glass, and ivory. They exchanged these things in India for cinnamon, frankincense, black pepper, and other spices, and for oranges, though by 300 AD people were beginning to grow oranges for themselves - even in Italy