Metrology learning and development is a complex field, but boiled down to its essentials, metrology is an understanding of units of measurement. This sounds simple, but it can be more complicated than it seems because there are multiple systems of measurement with different units used around the world. Here is a brief overview.
The metric system dates back to the late 18th century and was first developed in France. Basic metric units include the following:
- Length: Meter
- Volume: Liter
- Mass (commonly misunderstood as weight): Gram
Base units of the metric system are divided into multiples and submultiples of ten. These are identified by Greek prefixes. Therefore, even though the metric base unit of mass is the gram, most people use kilograms when expressing the mass of a human being. Similarly, the height of a human being is often expressed interchangeably as meters or centimeters. Because of its ease of use and scientific exactitude, most countries around the world have adopted the metric system.
British Imperial System
British imperial units are so called because they were the standard in the British Empire and its former colonies, including the United States. Unlike the metric system, which functions according to decimals, British imperial units are fairly arbitrary and do not have a direct relationship to one another. Take the measure of distance: One mile equals 1,760 yards, one yard equals three feet, and one foot equals 12 inches. There is no rhyme or reason to the measurement.
Current use of the British imperial system is uneven around the world. The United States still uses a version of the imperial system. However, because the current system was adopted after the American Revolution, U.S. customary measurements are based on an older version. For the most part, the United Kingdom has followed the rest of the world’s example and adopted the metric system. However, some units of the old imperial system are still in frequent use. For example, British people are at least as likely to describe someone’s mass in “stones,” an archaic imperial unit, as in kilograms.