The metric system is a system of measurement based on the decimal system. It involves length with units being millimeters, centimeters (10 millimeters), meter (100 centimeters), kilometer (1,000 meters). Mass is measured in milligrams, grams (1,000 milligrams), kilograms (1,000 grams), metric ton (1,000 kilograms). Temperature is measured in Celsius where the freezing of water is 0 degrees and boiling is 100 degrees. Area is measured in meters, hectare (10,000 square meters), and a square kilometer (100 Hectares). Volume is measured in milliliters, cubic centimeters, liters (1,000 milliliters), and cubic meters.