Originally, the pound1 was used almost across all the Europe, but later it was replaced by grams2 and kilograms after the international metric system had been accepted. Now the meter is the basic unit of length of the ISU3, and it consists of 1000 grams. Pounds and grams are common units but they belong to different systems, so if you ask people how many grams there are in one pound, not everybody will give you the right answer.
Different Types of Pounds
What is more, they can give you different variants, and many of them can be correct.
The point is that there are more than two weight systems. For example, according to the Avoirdupois Weight, one pound equals to 16 ounces and 454 grams (453.59). But the Troy Weight says that one pound has 12 ounces and 373 grams. In the USA and Great Britain the international avoirdupois pound is accepted (though this name is not very popular). So in these countries one pound is equal to 454 grams.
There are also some other weight systems (Tower, Merchant, London, etc) that have their own definitions of pounds. The following table will give help you to understand how many ounces and grams are in different pounds.
1 Avoirdupois pound
1 Troy pound
1 Tower pound
1 Merchant pound
1 London pound
The table below helps to convert international pounds and grams into some other units of weight.
Pound (abbr. lb) is a general unit of mass, which is used mostly in the USA, Great Britain, Canada and some other countries. It has many definitions, but the most known of them is equal to 454 metric grams.
Gram (abbr. g) is a widely-spread unit of mass from the International System of Units. One kilogram, which is the basin unit of the ISU, has 1000 grams.
The International System of Units (abbr. ISU, SI) is a modern system of measurement units, which is most widely used in the world. In consists of seven basic units: meters, kilograms, ampere, second, kelvin, mole, and candela).