Metric System

The metric system is a measuring system used by most countries in the world. It is based on the number 10, which makes it easy to use. Units include meters, grams, and liters.

How It Works

The metric system uses prefixes to show size. Kilo means 1,000. A kilometer is 1,000 meters. Centi means one hundredth. A centimeter is one hundredth of a meter. Milli means one thousandth.

Because everything is based on 10, you just move the decimal point to convert. One meter equals 100 centimeters. Easy!

Why It Is Popular

Almost every country in the world uses the metric system. Scientists everywhere use it because it is simple and consistent.

The United States is one of the few countries that mainly uses a different system. But American scientists and doctors use the metric system too.

Fun Facts

• The metric system was created in France in the 1790s during the French Revolution.
• Only three countries do not officially use the metric system: the United States, Liberia, and Myanmar.
• The prefix giga means one billion. A gigabyte is one billion bytes.

Did You Know?

One liter of water weighs exactly one kilogram. The metric system was designed so that different units connect to each other perfectly!