The History of measurement systems in Pakistan begins in early Indus Valley Civilization when pastoral societies used barter to exchange goods or services and needed units of measurement. The System of measurement is a set of units of measurement which can be used to specify anything which can be measured and were historically important, regulated and defined because of trade and internal commerce. In modern systems of measurement, some quantities are designated as base units, meaning all other needed units can be derived from them, whereas in the early and most historic eras, the units were given by fiat (see statutory law) by the ruling entities and were not necessarily well inter-related or self-consistent.