Why did the European population grow during the years 1100–1340, and what was the impact of that growth?

The population in Europe grew greatly during the 12th century because of greater food production. This is due partially to new inventions, which were developed around that time to aid agriculture. These inventions allowed more food to be grown more efficiently. People were able to grow bigger harvests, and they wasted less of the crops due to better harvesting techniques. Expanding trade with the rest of the world was also part of it, since that allowed more food to be imported to Europe. If, for instance, there was a shortage of grain, people could simply buy grain from another country at the market, exchanging non-food items like handicrafts or surplus food items like local vegetables. The result was that people died of starvation less often, and were able to support more children, creating a population boom over the 12th and 13th centuries.