The actual money in use in almost every country to-day consists of a wide and confusing variety: gold, silver, nickel, copper, paper in various forms, issued by various authorities under various conditions as to amount and as to seigniorage.

But among all the kinds, in each country some one kind is found standing preeminent and in a peculiar position, as the _standard_ money to which the value of all the other kinds of money is in some manner adjusted.

Usually this standard money is composed of a material (gold or silver) which is a commodity; but there are many examples of paper money being for the time the standard.

The difficulties of the money problem must be attacked at the point of standard-commodity money, where it is nearest to ordinary value problems and is less complicated than when the various other kinds of money and the various money substitutes are included.
We mean by standard money that kind, no matter what its form, which serves in any country as the unit in which the value of other kinds of money is expressed.

The standard usually is a quantity of metal of a certain weight and fineness, which, as a commodity, has a value also in industrial uses.