Much of Aztec life, just like the life of other Middle American peoples before them, was controlled by time.

The Aztecs had two calendars: the solar calendar and the religious calendar. Each day was controlled by two gods, each of which had a good and a bad aspect.

They used their calendars to know how to behave and what to do each day.

The time-measuring calendar was used to fix the best time for planting crops and other everyday activities

In the time-measuring calendar, one year had 365 days divided into 18 months. Each month had 20 days, and there were 5 extra days at the end of the year, which were thought to be bad-luck days and when disasters were most likely to happen.