Joseph B. Reid wrote: >The Encyclopaedia Britannica 11th Edition says: >"..the leading countries of the world (Great Britain and >India are the chief exceptions) have adopted decimal >coinage. The United States led the way (1786 and 1792) >with the dollar as the unit."
Depending on the subtleties of definition, the US currency is not truly decimal. It has two base units, cent and dollar, just like many currencies. It would be better for currencies to have just one base unit (and some effectively do). There are 100 cents in a dollar. The ratio of 100 to 1 between two base units is common in currencies. These concepts are why people call it 'decimal'. However, there are a couple of defects in implementing the concept: 1. Non-decimal coin - the 'quarter'. The label has no reference to either of the base units. More importantly, fractions have no place in a decimal system. The Canadian 'quarter' is marked in terms of one of the base units and it therefore looks more decimal. But the value chosen is still fractional. 2. Third base unit - the 'dime' This coin has no reference on it to either of the two base units. In this respect it is worse than the quarter. You just have to learn the conversion. Conceptually this makes it like a third base unit which happens to fit in between other base units (just like the 'Crown', 'Florin' etc did in the old UK currency). The Canadian version is marked in terms of cents.
