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.

These standard units can be divided into two separate groups: imperial and metric. Depending on where ... traditionally have used the imperial system of measurement. Despite being seen as quite ...

In prehistoric times, not much needed to be measured. You ate what you found and lived where you could. The […] ...

Metric measurements — also known as the International System of Units ... "Really, the only two letters left in the English alphabet were R and Q," Brown says. "And then you throw into the ...