Mexico uses the metric system, so distances are in kilometers, weights are in kilograms, gasoline is sold by the liter, and temperatures are given in Celsius.
Chiapas  is in U.S. Central Standard Time. Daylight Savings Time is observed April–October, though be aware that the hour switches on different days in Mexico and the United States.
Mexico uses the 60-cycle, 110-volt AC current common in the United States. Bring a surge protector if you plan to plug in a laptop.