Metric System vs. American System

To deal with the great variety of units of measure used around the world, in 1790, the French government set out to create a set of international units that would be used by all countries. In 1960, the metric system was coined the International System of Units because of its international acceptance. The metric system is the standard in almost every country except the United States. In addition, the metric system is used almost exclusively in scientific studies.

Temperature

The metric system measures temperature in degrees Celsius, while the American system uses degrees Fahrenheit. To convert degrees Fahrenheit to degrees Celsius, subtract 32 and multiply by 5/9. The Celsius system sets 0 degrees at the temperature that water freezes and 100 degrees as the temperature that water boils. Fahrenheit uses 0 as the temperature generated when salt is used to melt ice and 96 as the temperature of a healthy human.

Volume

Volume in the metric system is measured in liters. In the American system, volume is measured with cups, pints, quarts and gallons. A liter is equal to 1.05 quarts. In the American system, 2 cups equal a pint, 2 pints equal a quart and 4 quarts equal a gallon.

Distance

The metric system uses meters, while the American system uses inches, feet, yards and miles. A meter is equal to about 3.28 feet. In the American system, 12 inches equals a foot, 3 feet equals a yard and 1,720 yards equals a mile.

Mass

The metric system measures weight in grams, while the American system uses pounds and ounces. A gram is equal to 0.0022 pounds. A pound is equivalent to 16 ounces.

Advantages of the Metric System

The metric system is advantageous because there is only 1 base unit---grams, liters or meters---for each type of measurement and all of the others are related by a factor of 10, using prefixes in front of the base unit. From the base unit, the prefix deci- represents 1/10 the size, the prefix centi- represents 1/100 the size and the prefix milli-represents 1/1,000 of the size. To represent larger sizes, the prefix deca- represents an amount 10 times as big, the prefix hecta- represents an amount 100 times as big and the prefix kilo- represents an amount 1,000 times as big.