NARRATOR: The metric system is a way of measuring things. So with length, the metric measurements are millimetres, centimetres, metres and kilometres. A stamp, would be measured in millimetres.

No such simple relations existed in standard units of weight and measure among units of length (inches, feet, yards, miles) or among units of length, volume and weight. In other words, the French ...

the use of the traditional English system of weights and measures in nonbusiness activities. In 1866, Congress authorized, but did not mandate, the use of the metric system and, since 1975 ...