Although religion was the principal motivator in Aztec life, farming was the principal activity. Much of Aztec life was built around farming, which was extremely necessary to sustain the growing population. Since the land that the Aztecs farmed was not fertile enough to grow enough food to support the population, the Aztecs were forced to invent methods to increase productivity. These methods included irrigation, fertilizer, and even building terraces on hills that were previously not farmable. The truly original idea, however, was that of chinampas.
Chinampas were floating gardens built on swamps. The process of making chinampas was a relatively simple one. First, canals were built through the marshes and swamps. Then, the mud from the canals was placed on mats, which were made from weeds and straw. Then, trees were planted at the corners. When these trees took root, they secured the chinampa firmly in place. Once the floating island was secure and useable, the Aztecs used it to plant their principal crop: corn. They also grew various vegetables (such as avocados, beans, chili peppers, squash, and tomatoes), and sometimes—even flowers. Unfortunately, the Aztecs had no animals or machines to help them work the land. In fact, they didn't even have plows. Thus, it was even more necessary to have soft land. Luckily for the Aztecs, the chinampas were soft enough that it was possible to plant crops with nothing but pointed sticks.
After a crop (usually corn) was harvested, the Aztecs had several ways of dealing with it. One of the more common ways of preparing corn was to mash it with a round grinding stone (called mano) against a flat stone (called a metate). From this process, the Aztecs got a corn meal. This corn meal was used to prepare tortillas, which was the principal food of the lower classes. The upper classes also ate tortillas, but had other choices for food. These choices included turkeys, ducks, and geese. Since few of these animals were raised, they were considered a food reserved for the wealthy. Another source of food for the Aztecs was the maguey plant. The sap of the maguey plant was used to make a beer-like drink called pulque. Besides pulque, the maguey plant was also used for needles (the plant's thorns) and rope (made from the plant's fiber).