Centimeter

Definition: A centimeter (symbol: cm) is a unit of length in the International System of Units (SI), the current form of the metric system. It is defined as 1/100 meters. One centimeter is equal to 0.393701 inches.

History/origin: The prefix "centi-" indicates a hundredth, and therefore one centimeter is equal to one hundredth of a meter. Metric prefixes range from factors of 10^-18 to 10^18 based on a decimal system, with the base (in this case the meter) having no prefix and having a factor of 1. Learning some of the more commonly used metric prefixes, such as kilo-, mega-, giga-, tera-, centi-, milli-, micro-, and nano-, can be helpful for quickly navigating metric units.

Current use: The centimeter, like the meter, is used in all sorts of applications worldwide (in countries that have undergone metrication) in cases where a smaller denomination of the meter is required. Height is commonly measured in centimeters outside of countries like the United States. Centimeters are widely used in everyday measurements, construction, tailoring, and education. They provide a convenient scale for measuring objects that are too large for millimeters but too small for meters.

Millimeter

Definition: A millimeter (symbol: mm) is a unit of length in the International System of Units (SI). It is defined in terms of the meter, as 1/1000 of a meter, or the distance traveled by light in 1/299,792,458,000 of a second.

History/origin: The milli- prefix is one of many standard prefixes used in the metric system. It indicates one thousandth of the base unit, in this case the meter. The definition of the meter has changed over time, the current definition being based on the distance traveled by the speed of light in a given amount of time. The relationship between the meter and the millimeter is constant however. Prior to this definition, the meter was based on the length of a prototype meter bar. In 2019, the meter has been re-defined based on the changes made to the definition of a second.

Current use: Millimeters are often used in measuring small, precise dimensions in engineering, manufacturing, machining, and technical drawings. They are widely used in countries that have adopted the metric system. The millimeter is also commonly used to measure rainfall, snowfall, and other small measurements. In precision work, millimeters are preferred for their accuracy in measuring small objects and distances. They are standard units in construction, carpentry, metalworking, and scientific research.

Centimeter to Millimeter Conversion Table

How to Convert Centimeter to Millimeter